doing my brakes but stuck

[greenbastard]

i suprisingly have never done brakes before. i'm having trouble pushing the pistion back in on the caliper. how do you do that? can i do them without bleeding them? will this affect the ABS? i read on yahoo answers that you need a scanner to close the valve in the ABS or something. can some one help quick because it 12:30am and i want to drive my car tonight. i also don't have a C-clamp. i was told to use that but i don't have one.