Should be self explanatory. See what fits where and plug it in. Everything is keyed for the most part, just don't FORCE anything. It may take a strict push but so long as you don't force anything, you should get it going.
If you need greater help, take pictures of your gear and we can point it all out. Also, look up videos on YouTube about building a computer, that should give you more help than all the forums around because then you have picture AND explanation.