Something I learned recently is that we shouldn't over-upvote because this way we lose out 'voting power' as it's called. So, for example and nice, useful comment, you upvote - and simple 'thank you' or other like that, no - you're just 'wasting' a vote this way. Same goes with posts (that's why there's a 3'' limit between upvotes) but it mostly goes for the comments.
Also, resteem is apparently very important on steemit but that needs to be limited as well : if you have an account/profile and all you do is resteem for example, it might not work (even though it does for some). At the same time, if you never do, your reputation stays low and you don't get as many upvotes - balance is the key!
Last but not least: the reputation. It goes up very hard, but it's not impossible. You just have to comment a lot, upvote the posts you like, reply to comments, connect with your followers, and be nice to everyone. That last one might sound a bit 'fake' but the truth is that we're all here to socialize and to earn so nobody wants to be mean really...so that's easily doable!
I hope I kind of answered your question!! :) Let me know how it goes! I am quite new myself, but loving it already so always eager to learn (and I do, a lot, every single day!) :D