When reading various PHP related blogs, Quora questions, Google+ communities, newsletters and magazines, I often notice extreme polarization of skill. Questions are either at the "How do I connect to a MySQL database?" level or something in the range of "How do I best scale my mailing system to send over one million emails per hour without introducing a new server?"
I personally distinguish between 4 distinct levels of PHP prowess (likely applicable to any language/profession): beginner, intermediate, professional and elite.
In PHP, beginners learn about variables, includes, form processing. They learn simple logic constructs. They send an email with the help of a tutorial, maybe even touch on an object oriented programming example without actually understanding it. They work with WordPress and modify a couple CSS classes. With this knowledge, they apply for jobs and, unfortunately, usually fail.
Professionals are those who have given good parts of their lives to many projects. They've deployed commercial applications in most if not all frameworks, they've used different databases with PHP efficiently, they visited and/or talked at conferences. They studied design patterns and can easily engineer an entire project on their own from diagrams to execution. They left procedural code far behind.
Elite programmers are professionals who put in the fabled 10000+ hours into honing their skill. They supplement their PHP installations with extensions they wrote themselves, they find bugs just by glancing through source files, they are extremely meticulous about their code layout. They reject all but the most complex projects and find alternative and imaginative ways to solve problems people didn't even know they had. They've written some well received books about the language, spoke at dozens of conferences, maybe even made their own branch of PHP or a highly successful framework or two.
So in all this, who are the intermediate ones?
The missing link
How does one get from beginner to pro and beyond? If one doesn't know anything beyond the basics, how can they improve their skill enough to leave the bad practices behind and start practicing the more advanced approaches? This is a question I get asked a lot by beginners. In order to become a professional, one must first become intermediate.
What follows is a list of what one should go through on the path to PHP fluency.
Abandon spaghetti code
Many people think using classes means you're writing object oriented code, while using functions means you're writing procedural code. While this is false, for the sake of this argument, let's assume the widespread vanilla definition: procedural code is code in which you simply don't use classes and objects, and OOP code is code in which you use classes and objects as much as possible.
My advice is to fully abandon procedural code. Use object oriented coding style as much as possible – write classes, encapsulate logic, think with real world terminology. The performance benefit of procedural code over class based code is negligible when compared to the re-usability that proper OOP code gives you and future developers inheriting your project. A common argument against this is "But, WordPress is procedural!" To be frank, and this might sound harsh, "WordPress developers" are no more PHP developers than people with Instagram are photographers. Please don't take this to mean WP is useless – it's fantastic for blogs, simple websites and one-day projects you don't want to spend too much time on. It's excellent for making a quick buck or for people who aren't too technical, but mastering WP will never make you a professional PHP developer – it's a yarn of spaghetti code that can teach you no proper design principles.
Start small. Think of a real world concept, and try to represent it in OOP code. Work through some basic tutorials and slowly go more advanced. Work on OOP code until you understand classes in general before transitioning to proper frameworks and confusing terms like "Model", "View" and "Controller" – all these are foggy, abstract terms without having a solid foundation in OOP first.
Dissect existing projects
Dive into existing source code wherever you can find it. For example, look up PHP projects on Github, clone them, deploy them locally on your own machine and try to play around with the code. Go file by file, line by line, until you understand what each does.
Look for projects that are well commented and/or documented, well structured, and still alive. Projects last updated in 2008 won't do you much good if you're getting into PHP 5.5 – you'll likely be missing out on the latest and greatest features that could make you stand out in an already overpopulated field.
Learn to set up your own PHP environment
Being able to set up your own environment is a priceless skill. Not only does it allow you to fine tune your setup, it also familiarizes you with building extensions from source.
Abandon Windows for development – if your main desktop is Windows, install virtualization software and run a Linux virtual machine – the case insensitivity of Windows, its line endings, and all other oddities inconsistent with most server environments out there are just asking for trouble, so it's best to develop on a system that most resembles the environment you'll eventually be launching on.
Virtual machines also help you experiment – if something goes wrong, you can just wipe it and start over or do a rollback. You can literally experiment as much as you want without fear of messing anything up. Mastering tools is important, but having a good workbench is too.
Experimenting with your own setups will also allow you to get familiar with the different servers out there – whether to use Apache of Nginx, whether to use neither of them and go with Appserver, and so on.
Exercise best practices early
When writing your own code, make sure you comment heavily with docblocks, indent beautifully and structure carefully. After you build a class, project or library, use well known documentation tools (PHPDocumentor, ApiGen) to extract the docblocks and improve on them.
A good IDE is worth its disk size in gold – getting used to one multi platform editor can help you be up and running in no time when setting up a fresh environment, so you can dive into code instantly without wasting time on setting up keyboard shortcuts and themes. Make sure you back up IDE configuration files on a cloud service like Google Drive, so you have them ready for import at all times even if you need to make a fresh installation. A good IDE is PHPStorm, or if you can't afford it or have no open source projects with which to ask for a free license, Netbeans is a free alternative. Both are multi-platform.
Getting used to best practices early helps you remain consistent and lets other people read your code much more fluently. Find your style and stick to it – you'll help both yourself and others. Try to follow the PSR standards (PSR-0, PSR-1, PSR-2, PSR-3) as closely as possible – they’re called standards for a reason. Most of us use and love them, and they make everyone’s code equally reusable and readable.
A good beginner friendly resource that gives up-to-date hints is PHP the right way – use it to get familiar with the latest best practices, basics of OOP, security, deployment, coding standards I mentioned above, and much more.
Try out different frameworks, choose one
Having tried most of them, I can wholeheartedly recommend Phalcon as the go-to framework due to its robustness and quality, and the fact that it's built in C and installed as a PHP extension (thus being faster than any current framework in existence). However, trying out different frameworks is an absolute necessity.
When you try them out, you learn about a new approach to a common problem every time. Each framework has its own quirks you'll like and downsides you'll hate but most importantly, you'll learn about the mindset of others (particularly the developers of the framework). You'll see new usages and approaches, and a very good exercise is re-building one of your sample projects in as many frameworks as you can find. This will help you efficiently gauge the efficacy of a particular framework: the speed of developing in it and its performance.
Don't underestimate the hints and tips of others. Read as much as you can – if you keep at it, it doesn't take as much time as you might think. Find good blogs to follow, read the tutorials on this website, traverse questions and answers on StackOverflow, visit the SitePoint Forums, subscribe to newsletters, follow good sources on Google+. Avoid basic PHP tutorial books – they're outdated as soon as they're published – instead, focus on individual snippets and tutorials of useful up-to-date code you can find all over the web. Even if the topic is something you've already covered, try giving it a read – you'll often find that something new can be learned by reading someone else's perspective on the very same thing.
If there's no work, invent some
There is always something to do. Never catch yourself saying "I don't have a project" or even worse, "I'm bored". If you don't have an active project to work on – make one up. Do you use a tool daily that frustrates you with its lack of functionality? Build a better alternative! Have no ideas for new products? Replicate existing ones – try rebuilding a basic Facebook, recreate something you already know exists just for practice.
What's most important is to never stop – there's no amassing 10000 hours if you don't put in the hours! Keep working, keep yourself interested and engaged. Make a simple address book app. Then rebuild it in another framework. Then rebuild it with another database (replace MariaDB with Mongo, for example). Keep busy!
Find a buddy/mentor
It's easier to learn when you have someone to do it with. Find a buddy who shares your passion. Maybe you're one of the lucky few with a partner who shares your geeky interests. Maybe you're in school or university and have peers who would like to get started as well and need companionship in these adventures. You can even find a mentor and receive expert guidance.
Never underestimate the power of a companion – there's a reason The Doctor always has one!
When you focus on all these entries with as much will as you can muster, when you realize it's what you want and keep at it – you're on the road to becoming a PHP pro. Maintain discipline, never give up (even if others around you do) and keep practicing.
If you've got any useful resources you'd like to share with us on how you bridged (or are currently bridging) the Intermediate gap, let us know in the comments below!