#1 GET TO WRITING
Whatever your into, you should know the ins and outs, and get to writing short articles(300-500words) that would catch your target markets eye. You can distribute these articles through article directories or contact publishers to get them published on high ranking sites. Its best if you try both.
Get into social bookmarking and get your links on every social network you can. The key is to get your name out, be PROACTIVE! You are bound to get noticed. Its something free and useful so work on putting out a valuable offer.
#3 FORUMS ARE YOUR FRIENDS
Register and be active on relevant forums that have to do with your industry. This will promptly multiply your back-links, provided that they allow this and the links are doable. This is important, DONT spam forums with comments just to get back-links because you will get kicked off!
#4 FOLLOW A FEW BLOGS
Commenting on blogs is a great way to build links. All you have to go is follow some blogs that have to with your industry and leave a suitable comment in addition to leaving your link.
#5 BE UNIQUE!!!!
No one likes to see the same thing 500 times. If your different, exciting, informative, and even a little edgy, you will see great results.
#6 (MOST IMPORTANT) BE CONSISTENT!!!!!!
Make sure your in this for the long haul. Dont slack for a few months and say why am i not making money! Set a monthly target for how much you want to build. With hard work it will pay off BIG TIME!!!!