If it were possible to guarantee a rank in the top five, then everybody would be doing it. Only then, of course, more than five people would be using the techniques guaranteed to get them in the top five - but it would only work for five of them. In other words, this is an impossible question for anybody to answer.
Use good, sound, ethical SEO practices. Look at the sites that rank above yours and see where they are maybe better than yours; perhaps the content is better, or it's better structured? Can you change anything about your site to improve it?
And remember, SERP is fluid. It varies from day to day, place to place and depending on whether the user is logged in or not.