Check this thread out for some really good advice :
http://tfproject.org/tfp/showthread....threadid=11538
Quick summary : Be someplace safe with people you trust. Don't do more than you're comfortable doing (1 gram is more than enough). If you find yourself getting nervous/paranoid, take a few deep breaths, sit down, have some water and keep in mind that you might have some problems telling the difference between reality and a hallucination. Try to keep your wits about you, don't try to drive or fly, or jump into oncoming traffic. Just keep yourself in the most pleasant surroundings possible, sit back and enjoy the ride.