Clean and file your own nails. Put cuticles away and preferably wipe with an oil-free remover so that there is no grease on the nail surface. Measure the nails to make sure they fit each nail before gluing them on. You can file the false nails down to a perfect size beforehand. Line up the nails in front of you. Place a drop of glue on your own nail and on the loose nail, then attach the loose nail by moving it against the cuticle and pressing firmly. Hold for a few seconds so that no air bubbles form. When you need to remove the nails, the easiest way is to cut them down, file up the surface of the loose nail and then hold them in acetone so that the plastic dissolves. Never pull the nails off.