Hello,
It should not be too difficult. As a foreigner you will have to go through TSA background check. Visit TSA's Alien Flight Student Program website
www.flightschoolcandidates.gov for detailed information.
Additionally, you will need to get fingerprints taken in one of the TSA approved offices
http://www.tsc-csc.com/printoffices/. I am a greencard-holder and I am going though this process right now. It can be done in about one week and will cost about $204 ($130 TSA and $74 fingerprints).
Good luck.