The trick to this task is to have the right screwdriver that will fit. Here's a
screwdriver that most people will already have. It's a perfect fit and locks into the screw head which is recessed so it will stay in place and you can just turn it at will. The slot is quite deep so you will know when it is locked in. It also helps to have a mirror so that you can see the orientation of the slot to help position the screwdriver bit.