How to Lay Out Ceiling Tiles as Rock

Measure the ceiling tile's length and divide it in half. Use a metal ruler as a straight edge to score the tile down the center with a utility knife. Cut the ceiling tile's two halves in half so you have now cut the ceiling tile into quarters. If you wish to make a larger rock, cut the ceiling tile only in half or do not cut it at all and use the entire tile.

Draw the rock's outline onto a piece of cardboard. Cut the outline out with scissors to form a template. Lay the template on each of the ceiling tile pieces and trace around it with a marker.

Break the ceiling tiles with your hands, following the rock outline you traced onto the tile as closely as possible. Cut out tight corners and bends with a hobby knife. The tiles do not need to break precisely since the imperfections will form the rock's segmented layers.

Stack the layers on top of each other. Decide whether you like the rock's look. If you want to give the rock's top a pointed appearance, break the top few sections into gradually smaller pieces. If you leave the rock's top surface flat, it can be disguised with trees, bushes or other decorative items.

Insert a glue stick into a hot glue gun and turn the gun on. Wait a few minutes for the gun to heat the glue stick. Lay the bottom ceiling tile on a flat surface. Spread a layer of hot glue over the top surface and set the second ceiling tile layer on the bottom tile. Continue to glue the remaining layers in place.

Fine tune the rock's appearance with a hobby knife. Fill a small bottle about one quarter full of white glue. Finish filling the bottle with water and stir. Fill an eyedropper with the mixture and drip it over the rock's edges to remove loose particles and help blend the edges. Allow the rock to dry.

Spray an acrylic primer over the entire rock. Allow the primer to dry. Paint the entire rock with a latex paint of either brown or gray. Touch up the edges with different colored browns or grays to give the rock a realistic look.