Ever need to get a screw into a tight place? The screw may be too small to get your fingers and the screw driver on it at the same time. Other times it fits into a corner or crevice and there is just no room to get your fingers in there to hold it in place while you get the screw started. I have a special screwdriver that has a split blade which you can twist so that if fits tightly into the screw head to hold it. But I can never seem to find it when I need it and it only works with slotted head screws. So instead I revert to a couple of tips my Dad taught me decades ago. The first tip is the more general of the two applying to all kinds of screws.
Friction Method
Tear off a small piece of paper towel. In this case I am using a fairly thick shop towel. If your paper towels are too thin just fold it over to double the thichness.
Place the paper on the head of the screw and instert the screw driver. If the screw doesn't stay, try folding the paper over. What you are trying to do is create a very tight fit between the screw head slot and the screw driver tip.
This technique works for both phillips head screws as I've demonstrated with the wood screw as well as with slotted screws as demonstrated with the short sheet metal screw below. Be sure to use the proper sized screwdriver for the screw. Otherwise, you may have too much slop between the screw head and the driver tip to get a tight enough fit.
Magnetic Screw Driver
Some screwdrivers come with a magnetic tip. This is handy for holding ferrous metal screws. However, you can easily magnetize any screwdriver made of ordinary tool steel. First, find a strong magnet. I simply use the magnetic tool tray I keep on my workbench.

Then rub the shaft of the screwdriver across the magnet about ten times.
Ta daaah! You now have a magnetic screw driver. It isn't permanent, but it will last long enough for you to put that pesky screw in place. Of course, this technique works only with ferrous screws and therefore will not work with brass or most stainless steel screws.