For the record, I consider myself to be in the "tight stage" right now and I've been there for a couple years now. I'm learning to be aggressive, but I'm still not comfotable risking large amounts of money in any one single bet. One way I have recently taught myself to be more aggressive and comfortable with large bets is to play No Limit and Pot Limit stakes. After calling some large bets and making large bets and raises of my own, a capped round of betting in a 5-10 holdem game doesn't seem that difficult. (Here comes stage 3!!! ha ha)
Random thoughts from a lawyer, an accountant, a commodities trader, an ex-Marine and a WSOP Main Event money finisher that don't know as much as they wish they did...