Oy! what to do

Ok so, most of you know I work as an independent contractor at a massage therapy business. The thing is the business owner is a total jerkface. She requires us to be there certain hours, even when we have no appointments on the schedule. Mind you, independent contractors only get paid when work is done. So essentially, we get paid nothing on the days when we sit there and there is no business. This is not legal. But causing a stink about it will end in her terminating my contract because she's just like that. She treats us like employees because she can get what she wants that way. She calls us independent contractors so she doesn't have to pay certain taxes. She's trying to have her cake and eat it too...with extra frosting.
She's starting to take percentages of our tips if they are more than 20%
She has been over charging us for sheets, so she makes a profit.
She has made us do free massages for promotions she signs us up for without our consent.

Oy! How does one start at putting a stop to this. I need an attorney... but that will cost me. I make good money there, the owner is just illegal, immoral, and just plain horrible.