Oh dear I'm not very good at explaining things, but I'll try to help you. When you see a post you like you can good Rep that person. When you see a post you don't like you can bad Rep that person. Look at the bottom of your post under where it says vCash. In your post if I wanted to Rep you for that post I would click on the 4th symbol. Take a good look at that symbol because not all posts have the same symbols. When you clink on the Rep symbol a screen
will come up asking you if you approve or disapprove of the post. You clink on whichever one it is and there is a space for a comment if you wish to make one and then I believe it says submit. And when you click on that you have Repped somebody. I hope this helped at least some as you can see I'm not very good at explaining things
Oh BTW you can find your Rep History in your control panel called "User CP".