Go to quests & achievements to see different ways to earn gems and dollars. It changes 1-2x/day.

In this game your status is constantly changing based on how other players are doing. In other words you get points for every outfit you submit. The more outfits you submit the more points you get and when I say points I mean Stars. If other players are submitting a lot of outfits and you are not of course they're going to have more points