If you are stripping Phillips head screws a lot try finding a screwdriver one size larger. I tell people to find the screwdriver that looks like the right size

If you are stripping Phillips head screws a lot try finding a screwdriver one size larger. I tell people to find the screwdriver that looks like the right size and then go one size up. The head should be snug in the screw, if it is not you are far more likely to strip it. Also pay attention because some Phillips head screwdrivers are pointy and some are more flat tipped. Using a pointy screwdriver on a flat type screw is a good way to strip them. With the right tools you will almost never strip a Philips head screw that isn't rusty or glued in. In the latter case you're more likely to snap the head off entirely than to strip it. Finally, when removing the screw remember to push down on it (yes this seems counterproductive) to avoid slipping out of the hole. Guarantee doesn't include cases where the knucklehead before you used the wrong screwdriver and rounded the crap out of the screw head.