Here's a trick someone taught me awhile back. Use a bowl and right before you're done with your hit, cover it with a matchbook or something to put it out and hold it there for a second. No smoke will go in the air. Also, take small enough hits so when you blow it out, little to no smoke should come out of your mouth. That's the beauty of smoking and conserving our wonderful little gift of mary jane. You want as little smoke to go in the air as possible, because it's not true that whatever smoke you blow out already has the THC gone. And any smoke that you see going up in the air is money. All your money is going up in smoke and you're wasting it. But if you really don't wanna have to worry about smoke, just take some E, it'll mellow you out alot more =P