There will be no links to PS articles in this post I promise you.

Per card as you know it is about 1 in 5 to hit a flush draw. Simple, 9 cards help u and 39 don't. To deny him direct pot odds you only need to bet a bit more than 1/4 of the pot. Same will work for OESD.

However, this isn't the entire truth. This does not take into account implied odds. Not so much for flushes but for straights if your opponent hits often it won't be apparent and you will pay out more money (as you should). If you bet more than 20% of your stack then he wont have the implied odds either.

In a typical SNG it does not take much to destroy the pot odds and implied odds of draws. If the blinds are 15/30 and you have a 1500 stack then you raise to 90 or 120 and get one caller. The pot is already 300. Betting potsize on the flop and half potsize on the turn is enough to destroy the pot odds and implied odds as well.

Also if you put your opponent on a draw and it misses, dont forget to check the river for value if you are out of position