Sort:  

Hi mattytripps,
From what I've learned so far, I'm relatively new here, you earn steem dollars by making posts with good content, good content leads to more people reading your post, in turn more people upvote your post.

Upvoting your post gets you money and if your post is very popular you could end up on the 'trending' page where you can make quite a lot of money. There are many other ways to make steem dollars on here too, like play steemit poker, competitions in many of the categories and more.

I believe you can purchase steem dollars with bitcoin but I'm not sure how that process works so maybe someone with more knowledge will stop by and help you out with that part.