Fiberglass doors are very popular because of their durability and lightness compared with other door construction materials. You can decorate fiberglass doors with blinds or other accessories that require screw holes for mounting. Fiberglass is harder and stronger than wood but can just as easily be drilled into using wood drill bits. The fiberglass will dull drill bits out fast and generally require pilot holes when drilling holes any bigger than 1/8 inch.
Mark where the drill holes are going to go using a tape measure and a pencil. Double-check your measurements.
Put the point of a large nail on the marks and tap it with a hammer forming an indent in the fiberglass. Do this to every mark to assure the drill bit goes in at the exact point you want it to.
Put on safety glasses and drill pilot holes on the marks that are half the size of the final holes using an electric drill. To avoid drilling through both sides of the door, wrap the drill bits in masking tape, allowing only 1/2 inch of the tip to show.
Drill the holes to the final size using the electric drill. Countersink the holes using the correct size of countersink drill bit, this will allow the head of the screw to sink into the fiberglass and sit flush.