Purchase a sheet of acrylic, Swedish plastic, hobby plastic, or even a tube of Krazy Glue. Each one of these products makes a great fake nail. Using a small pair of sharp scissors, cut out pieces of the product in the shape of your finger nails. Even the outer tube of the Krazy Glue is a convenient and effective material. It has a natural curve that fits over the curve of your finger.
Start by cutting small strips from your material, creating shapes to resemble the curve of your fingernail. You will have to do some forming in order to get the nail material into a perfect fit.
Acrylic nails are by far the strongest and longest-lasting fake nail. Nail salons and dental offices fabricate great-looking fake nails made from acrylic. Plastic nails purchased in any drug store also make great-looking fake nails.
Blow dry the plastic or acrylic material. The heat relaxes the plastic so it bends easier over the nail. Don't heat it up too much, or it won't keep a shape. Just warm it up enough to add a little pliability.
Use Krazy Glue, rubber cement, or contact cement as a nail adhesive. Krazy Glue adheres fast, but the nails are harder to get off. Cements are effective adhesives also. They also hold the fake nails on well, and are easier to remove later on.