You can buy calipers from your local hardware store. Don’t include the threading in your diameter measurement. Otherwise, the hole you drill will be too big and the screw will slip out.
You can buy a set of multiple drill bits from your local hardware store. There are many tables and guides online that specify how big pilot holes need to be depending on what size screw you have.
Try pushing the piece of wood to see if it moves or shifts. If it does, put another C-clamp on the opposite side.
If you aren’t able to make a dent in the wood with the screw by itself, lightly tap on the screw’s head with a hammer.
Wear safety glasses while you drill your hole so you don’t get sawdust in your eyes. Don’t force the drill bit into the wood since you could cause it to break, and you could seriously hurt yourself. If you want an easy reminder of how deep you need to drill, wrap a piece of masking tape around the drill bit so it’s at the same length as the screw. That way, you won’t be able to push the drill any farther than you need to.
You can buy a countersink cutter from your local hardware store. You can also get countersink cutters with a flat bottom if the screws you’re using don’t have an angled head.
Put on safety glasses while you’re drilling to protect your eyes in case the cutter breaks or comes loose. Don’t force the countersink cutter into the wood since you could make the hole too deep or damage the bit.
You can drive the screw further into the wood if you want to conceal it later on.
You can buy wood putty from your local hardware store. You will not be able to remove the screw if you cover it with putty. Only use putty if you want the screw to be permanent.
Some wood putties come with a hardening agent to help promote faster drying. Mix the hardening agent with the putty before you apply it for it to take effect.
You can use an electric sander to speed up the process if you want, but it’s not required. If you do, wear a dust mask so you don’t breathe any sawdust.
