Is it better to try to raise and get as much money into the pot against draws or keep it small?
If you don't charge them to chase, then it's your own fault if they hit.
This assumes that you have a made hand to begin with, and that you can fold when it's obvious that they did hit.
Standard raise in a tournament/SnG situation might be just over 1/2 pot. In a cash game if the stacks are bigger you might want to go closer to 3/4 to full pot because of the larger implied odds with the bigger stacks.
Odds of filling the flush are just over 4 to 1, so if you bet 50 into a 100 pot, a single opponent has to put 50 in to win 150 so they aren't getting odds to call, again assuming that you don't pay them off when it does hit. It gets trickier if you have more than one opponent still in the hand as if one calls, it gives then next one better odds.
You make money when your opponent makes mistakes. If he chases flush draws against the odds, then you're winning in the longer term. If you don't bet enough and give him odds to chase, then you're making the mistake.