Things You'll Need
Ruler or measuring tape
Electric drill with variable speed settings
Sharp twist bit of appropriate size for desired hole diameter
Drilling holes in plastic may seem like an easy task, but plastic is a brittle material and is prone to crack and splinter if you aren't careful. Knowing the proper drilling technique for making holes in plastic can save you a lot of headaches and ensure that your holes are clean and evenly cut.
Measure and mark the area where you will be drilling with a ruler or measuring tape. Be sure your measuring and markings are precise because once the hole has been drilled there is no easy way to undo it.
Insert a sharp twist bit into the drill and tighten the bit in place. Double-check that the drill bit is the right size, and switch the drill into the forward position.
Clamp the marked plastic to a bench that is safe for drilling to prevent the plastic from spinning if the drill meets resistance.
Set the drill to its slowest setting, if it has a variable knob. Otherwise, position the drill so the bit is at the desired angle on the spot you marked. Depress the trigger as lightly as possible and drill a hole very slowly through the plastic.
Watch the area around the hole carefully as you drill. Stop drilling and allow the plastic to cool if you begin to see the plastic shavings around the hole gumming up.
Set the drill to the reverse setting and slowly pull the drill bit out of the completed hole.
Gently sand the area around the hole, being careful not to scuff the plastic in the process. Check for any cracks or splinters that might affect the integrity of the plastic before putting it to use.
When in doubt, use a smaller size drill bit. You can always increase the size of the hole with a larger bit later but you can't make the hole smaller.
Always wear the appropriate safety gear and work in a safe environment when using power tools.