I try to refrain from snacking as much as possible. (It's hard with a fast metabolism, trust me.)
Normally I just eat as much as I can during breakfast, kind of let myself sit for a bit, and then go out and do stuff. Only push myself into doing something that'll burn it off faster if I have to...drink water if I start to get kind of hungry. Hunger and thirst go hand and hand with me, so if I'm hungry, I'm likely thirsty too.
And then I stuff my gob at dinner.