If you can't make the money from your job, you are only left with a few options. First option is to sell or pawn your stuff. Go through and find things of value that you don't want, and try and sell them. Pawn shops will by a lot of things, but don't expect to get what you want out of the items (they have to make money on it too). You can pawn items that you don't want to sell, and would like to get back, but you will have to pay the money back pretty quickly, plus a good ammount of interest. The other option is to borrow from friends and family, or get a loan from the bank. A bank loan might be tough to get making minimum wage ( NEVER EVER go to a payday loan specialist, or call the loan advertisements you see on TV). Hope this helps a bit.
That's a lot of money to make in 20 days. Short of selling things you own or doing lots and lots of babysitting, mowing lawns or door to door sales of certain items, that will be hard to do.
Sell a lot of stuff. Mow lots of lawns. Ask for overtime at work.
Stock market.