Check out this Article, it has plenty of links to other peoples posts that answer most of the questions you can have about steemit:
https://steemit.com/steem/@msutyler/10-links-for-steemit-beginners-how-it-works-difference-between-steem-power-and-dollars-how-to-add-images-etc
Other than that I would highly recommend you actively research cryptocurrencies. Its a very complicated field and is heavily intwined with Steemit. You can find a ton of amazing investment opportunities if you keep up to date, although personally all my major investments are in 1st rate coins such as Bitcoin, Ethereum, Litecoin, and Steem