AOPA has a good guide to the process.
http://www.aopa.org/tsa_rule/
I went through the TSA deal with a foreign (Canadian) student and it wasn't that bad. It took some research and some phone calls to find a place that would do his fingerprints, but overall it was pretty simple.
My advise it to stick with the process and recognize that it'll take a month or two before you can start flying.
Basically:
You register as a training provider with the TSA.
Your student registers as an alien seeking flight training and selects you as their training provider.
You confirm.
The student completes paperwork.
The TSA sends a preliminary approval, which doesn't mean you can start training.
Your student gets fingerprinted and sends in $135.
The TSA gives their blessing.
You collect a bunch of documents from your student, take their picture and upload it to the TSA and you start training.
All of this, with the exception of the fingerprinting, takes place online.
Good luck!