I prefer the set-it-and-leave-it method. Determine the pressure you need to achieve the correct volume of CO2 for the style of beer/temp of fridge. Set the regulator at that pressure. You can leave it that way for 5-7 days for the CO2 to equalize on its own, or you can shake/rock the keg under pressure for a couple of minutes twice a day for the first couple of days. By the third day mine are usually ready. I never mess with the regulator after the initial setting.
Setting the pressure too high to force carbonate faster can result in foamy beer if you're not careful. But there are differing thoughts on the matter and I'm sure plenty of people will chime in.
Edit: By the way, I drink my beer relatively slowly. A keg will likely last more than a month in my fridge. If you carbonate at one pressure and then set it higher or lower to serve, eventually the CO2 will equalize at the new pressure... changing the volumes of CO2 in the beer.