How to write a good Statement of Purpose (SOP) letter?

After four years of Neetdom and depression, I've decided to join a university. I've nothing to show what I did in these four years except some programming and drawing. Also, my grades aren't good just above average. I'm thinking to do ms in computer science. So, my goal is to write a good SOP that can compel the reader to think that I'm serious and I want to do it. Any advice, suggestions, links are welcome.

>>10195 I don't think they explicitly ask for your age, but it may show up on any transcript you send them. Whether or not they check for a gap, I don't know. I assume you have a bachelors if you're trying a masters program. Programming will probably look good. The following may help, http://matt.might.net/articles/how-to-apply-and-get-in-to-graduate-school-in-science-mathematics-engineering-or-computer-science/

>>10196 >Whether or not they check for a gap, I don't know I think they'll ask this in visa interview >I assume you have a bachelors if you're trying a masters program. Yes. Thanks for the link.

>just above average my friend I am barely keeping scholar ships in a design degree because I failed out of computer science. im betting what you mean by "just above average" is probably better than most people.