Mentally, the approach should be one where you are capable of ejecting. Sure, see some flops, but be prepared to fold out if it isn't there for you.
In mid-tournament stages, for example, 40bb is going to be a solid stack. Getting in pre for 2.5 is one thing. Sure, if you hit the flop, etc., you could take down a 10bb pot. However, if you play it out and lose, you could drop 10bb as well... and that's 25% of your stack. But folding out those 2.5bb when you do not hit, only costs you those 2.5bb. You can do that 4 times before you lose that 25% of your 40. And one of those hands might be one where you add on the 10bb.
One mantra I have used to match this is "trickle down; jump up."
So you don't have to tighten up horribly pre-flop. But again, be prepared to eject if you don't hit. Don't speculate, don't wish, don't c-bet into 5 people with complete air. Just give yourself opportunities and take advantage when they come.