calculating whether to play a drawing hand

I'd like some advice on how to quickly determine my odds of hitting a drawing hand after the flop and how to use that information in deciding whether to call. I know I have to be getting the right odds, but I need to know a quick way to figure that out - This for use in a live game - not online. Thanks for any help.

The rule of 2 and 4 is probably the quickest and easiest way to estimate your chance of winning so that you can compare that to the pot odds you're getting:

http://www.flopturnriver.com/phpBB2/...ht-t39853.html

http://www.learn-texas-holdem.com/ti...e-for-odds.htm