When I started playing online poker I followed a lot of the bankroll management guidelines that Chris Ferguson talks about…5% on sng’s 2% on mtt’s and so far it has been pretty successful.  It took a lot of discipline for me to play with less than 5% because the pay is just never good enough unless you hit a big mtt, but it easier to handle the downswings when you’re not cashing.  I still buy in with less than 5% on sng’s and less than 2% mtt’s.  Sometimes if I want to step out of my bankroll and play an expensive tournament I will try to satellite into it that way it won’t hurt the roll.  I feel that it would be very hard for any half decent player to go bust if they followed his guidelines. 
-this is my first post here-