Buy a freaking bicycle pump and keep it in your trunk along with a pressure gauge, that's what I've done for years, works perfectly for adjustments. ~15-25 pumps = ~2-4 psi.
With regard to what psi to run, run whatever feels good to you that's at least the factory recommended, and at most the max cold psi stamped on the side of the tire (though that will probably feel absurdly stiff).
Air it up to factory spec and play in 2psi increments to find something you like. Depending on the tire, I've run anywhere from 31-45psi (Continental Extreme Contact DW's have absurdly soft sidewalls)
Last edited by TheOneDoubleN; 12-13-2012 at 10:31 PM..