When using a screwdriver, these are what you should do:
First, make sure you select the right kind for the job. If not, you may either ruin a perfectly healthy screwdriver or strip the screw head and make it difficult to remove later, if you have to.
Secondly, fastener heads may have a single slot, a slotted cross, a hex-shaped indentation, a star pattern, and other shapes. So be sure to examine the head of the screw or fastener to match it to the correct screwdriver. Never use a flat-head screwdriver on a Phillips-head screw. Even if you do get by with this combination a few times, you are risking damage to both the screw as well as the screwdriver.
Next, confirm the tip of the screwdriver completely fills the screw head you are driving or removing. If the tip is too narrow, you will lose considerable torque and leverage while driving, and that means you have to put in more effort to complete the job. Additionally, you risk bending the tip of your screwdriver and/or stripping the screw head.
If the tip of your screwdriver is wider than the screw head, it may damage the surface you are screwing into. If the tip is too thick, the blade will not be able to drive the screw, as it will simply slip out. To use the right screwdriver for the job, you can use a suitable screwdriver-sizing chart such as below.
Slot-headed Screwdrivers and Screws
| Blade Size | Screw Size |
| 3/32” | O and 1 |
| 1/8” | 2 |
| 5/32” | 3 |
| 3/16” | 4 and 5 |
| 1/4” | 6 and 7 |
| 5/16” | 8 to 10 |
| 3/8” | 12 to 14 |
| 7/16” | 16 to 18 |
| 1/2” | 18 to 24 |
Phillips-head Screwdrivers and Screws
| Blade Size | Screw Size |
| 0 | O and 1 |
| 1 | 2 to 4 |
| 2 | 5 to 9 |
| 3 | 10 to 16 |
| 4 | 18 to 24 |
Remember, when driving screws into wood, it’s a good idea to drill a pilot hole first. Without pilot holes, screws tend to follow the grain of the wood, which results in crooked screws. The pilot hole can guide the screw into the wood and allows it to enter straight. In addition, the pilot hole prevents the wood from splitting as you drive the screw in. Place the screw in the pilot hole, hold it with your fingers and apply a little pressure with the screwdriver as you turn the screw. If the area around the screw is insufficient for holding it with fingers, you can use a screw holder.
