How to Apply Prepasted Wallpaper

Prepare the room you will be working in by removing the furniture and laying down a drop cloth. Turn off the power to the room and remove any light fixtures, light switches and outlet covers from the walls. Set up a large table to work on.

Prepare the walls if needed by sanding down rough textures, fixing cracks or uneven spots, and removing old wallpaper if it is damaged.

Clean the walls with TSP and apply a 100 percent acrylic pre-wall covering primer. According to "Reader's Digest," this gives you more time to adjust the paper while hanging it, and it helps prevent shrinking.

Plan out the direction you will move around the room so that you end in the least noticeable spot. The last piece of wallpaper will not match the pattern on the piece beside it, so let it end behind a door or in a dark corner.

Measure the height of the wall from floor to ceiling and add 2 to 3 inches to each end, 4 to 6 inches total, to create overlap between wall, floor and ceiling in your wallpaper strips.

Unroll the wallpaper and measure out your first strip, remembering to add in the 4 to 6 inches for overlap. Cut this piece of paper and continue to cut off 2 to 3 more strips.

Use a sponge to dab water onto the back of the wallpaper strips. This will activate the paste.

Lay the wallpaper onto the table with the paste side up and fold one end toward the middle. Fold the other end in into the middle. Start at one end and roll the strip up, placing it in a plastic bag. Leave the paper there for 5 to 15 minutes as stated on the manufacturer's instructions. This process, known as booking, allows the paper to relax without drying out. If you skip this step, your wallpaper may shrink on the wall and fall off or leave gaps.

Measure out from the door frame, or area you are starting from, the width of one wallpaper strip and use a level and pencil to draw a straight line from the ceiling to the floor. Measure over from this line the width of one strip and draw a second line. Continue measuring and marking in this way around the room.

Remove the first strip from the plastic bag and take it over to the wall. Using a ladder and a friend's help if necessary, place the wallpaper strip onto the wall. Make sure to line the edge up with the line that you drew. There should be some overhang at the top and bottom. Push the paper up against the ceiling and floor, and use a wallpaper smoother to smooth out the wrinkles.

Trim away excess paper at the top and bottom of the strip with a utility knife. Use a broad knife as a guide to keep the utility knife from slipping.

Take the next strip of wallpaper and align it so the pattern matches up with the edge of the last strip. Apply this piece of wallpaper in the same fashion as you did the previous piece. Trim away the excess paper.

Use a seam roller on the seam created between the two pieces of paper. Use the wallpaper smoother again on the two pieces if any bumps or uneven spots appear. Continue this process with the rest of the wallpaper strips until the room is complete. You may need to trim down the width of the last strip so it will fit.