To install a shower liner, first cut a hole in the center of the shower floor to make space for the drain assembly, then install the liner material from the drain outwards, nailing it into place 9 inches above the edge of the floor. Test the installation by filling the basin with water and letting it sit for four hours while checking for leaks.
Pre-measure shower liner to the area of the shower basin, and attach it to the framing studs of the shower. In some cases, it is necessary to seam together two pieces of liner material, necessitating the use of a special solvent that glues the liner together and forms a waterproof bond. When laying the liner on the shower floor, work around the drain, arriving at the perimeter of the shower basin floor and lapping the edge of the liner completely over the basin's curb, then nailing the excess liner to the outside edge of the curb.
If a leak is discovered when testing the installed liner, drain the water, and repair the leak before attempting to test the liner again. Make sure the liner is completely leak-free before setting tiles or other flooring into place to complete the shower basin.