The question in the title is pretty much it. What would you suggest would be the best SEO technique for a new site?
Write good content that is easy to read and which provides information that cannot be easily found all in one place on other sites.
I consider a lot of good SEO technique for me and I can’t really say that there is the best or most effective as I find all beneficial… not same in quantity at times though… if I would have to pick however, I will say that I would agree with ^… content is the best way to get traffic and it is the best way to get them to convert into ROI…
write good content and define title tag, description, keywords.
In my experience, updating your unique content and focus in all off page optimization. Then traffic will follow and will improve your rankings in Google 
I would go with On-page optimization first. Getting back-links also matters but doing a proper on-page optimization is really a good technique.
I suggest you should better have a brief look at all the On page factors such as Title, Meta tags, Content, Alt tags and Internal links too.
Good use of on page SEO is very important such as using the right keywords you want people to you with, the placement of of those keywords, making them bold etc.
I have wrote a good guide on SEO which you can find here: Search Engine Optimization
It’s sort of like a check list with all the key points.
Search Engine Optimization is a complex subject and difficult to sum up in such brief words but for starting out its a useful little guide.
Include a keyword in the title tag and meta tags. In your website’s source code you will get various meta tags such as Title, Description and Keyword tags.
Avoid keyword stuffing.
Try to have content relevant to your site’s main page.
(Link Building) link out to other sites, they will link back to you.
Be active on social Media and social bookmarking sites e.g Twitter, Facebook, LinkedIn, Delicious, Digg, StumbleUpon etc.
Be Useful.
I think it must be forum posting… he he he…
Don’t overlook the additional FREE tools such as “Google Webmaster Tools”. No one’s mentioned this yet but with GWT, Google Analytics and all the on-site SEO, for me that’s when you know you’re doing a really good job. GWT put to good use is basically helping Google to do a better job of indexing your site and being pro-active to anything GWT shows up as a little ‘glitch’.
So for me, it’s not just about straight up META. It should be much more of an analytical, multi-tool awareness operation.
Thanks,
Richard.
Keyword reach unique content because content is king and also Social Bookmarking because social bookmarking gives temporary but good hike to your website.
Good content and updation of the content frequently are of utmost important. Daily updation would really help.
Why?
I should point out that I completely disagree with you because I can’t think of a single reason why the frequency of your content changes would be a sign to Google that you have a good website but I’d like to hear your reasons for saying that?
One of the most effective techniques is to use keywords in the title tag. Seems simple, but so many sites don’t do it.
write very effective content because content is the king and create more content for article. press release and news and submit it with u can motivate your new site and increase lead and traffic.
Perfect. I was going to say the same thing but using far more words, you’ve summed it up in a nutshell.
Writing Fresh Content with proper guidelines like Metadata tag, Keyword and Social Bookmarking, Networking is good according to me. However you can get quality back links to your site, it will benefits you also.
According to Google Webmaster Blog,
Create unique and compelling content on your site and the web in general.
All of optimization depends on Content. Make it good enough to grab attention and leave the rest to Google.
Thanks