You mean like sober up? Coffee really does it for me combined with "acting sober" which I think everyone should do in polite society. Same with people who drink, I can get totally shit faced and talk correctly. Most that happens is I revert to basic speech mode. 3 word sentences and such that are just the gist of what I mean to say.

Edit: oops, that was irrelivent, just be physically active on a regular basis, get stoned and weight train or run, swim, really work the lungs, and only blaze so often. Shoot, give a few weeks to getting in shape and when you toke you'll be higher than ever for longer.