I've read alot articles about potodds on the internet, but something I never seem find is a quick way to figure out if you're draw is +EV.
Sure you look at the bet/(pot+bet) and at your outs, but what do you do after that?

After some fast math I came to this conclusion:
4Flushdraw: Flop: pot Turn: 1/2 pot
4Straightdraw (or double bellybuster): Flop: 3/4 pot Turn: 3/8 pot
I know this isn't exactly precise, but is it even close to the real results??

Also, when you know these do you always have to bet more then that when you want to make someone's draw to expensive. If my calculation is right that would mean that you would have to bet more than the pot everytime there are two suited cards on a board you've hit?. That can't be right.

I'm totally confused now, can anyone help me please?