Replacing a headliner in your car generally involves removing the car part attached to the headliner, pulling it out, cleaning the headliner shell, mounting a new headliner, and reinstalling the removed parts. A pair of scissors, a screwdriver, a large grit sandpaper and spray glue adhesive are handy in the replacement. Wear protective gear while working.
To replace the headliner, first place a protective sheet over the seats, dashboard, wheel and other interior parts of the car. Pry off the visors, remove the coat hanger, and take out the lights from the headliner, unfastening them with a screwdriver if necessary. Use your hands to pull out the headliner. Clean foam off the headliner shell with a large grit sandpaper.
Put the new headliner fabric on the shell, and fold the headliner over on itself to expose a section of the shell. Spray adhesive on the backside of the new headliner fabric, apply some glue on the shell, allow them to dry according the manufacturer's instructions, and fix the glued part of the fabric to the shell. Fold the other side of the fabric, glue as appropriate, and secure it to the shell. Be sure to level the fabric. Cut off the overhang.
Replace the headliner moldings, reattach the hangers, put the lights back in place, and reinstall the visors. Uncover the wheel, dashboard and seats.