you need to understand anchor text first, you know when you are on a webpage and you see some highlighted text usually in blue that is clickable, the keyword that you see is anchor text.

now when you want to rank for a keyword you want that keyword to be your anchor text. so remember that no matter what your method of backlinks are use the correct anchor text.

some backlink methods are forum and blog posting, social bookmarking, pinging, you can buy backlink packets (from wso) and manually subit your anchor text, article submission etc etc

hope this helps