Step 1
Vacuum the carpet.
Step 2
Use a utility knife to make a half-inch cut on one side of the bubble. Make sure the cut is between two rows of fibers. You might have to look closely at the carpet and push fibers apart with your fingers to see the space between the rows.
Step 3
Insert carpet glue into the bubble, starting at the back of the bubble. Some flooring repair glues come with a tapered nozzle for easy insertion. If you're dealing with a large container of carpet adhesive, pour 1/4 cup of the glue into a disposable cup. Dip a cotton swab or other applicator into the adhesive, and use it to apply the glue. Press the bubble down with your fingers as you work from back to front. Do not apply so much glue that it oozes from the bubble.
Step 4
Seal the seam you cut with a carpet seam sealer. Follow your seam sealer's instructions for application rates. Use the seam sealer's applicator tip for application. Apply a line of sealer along one edge of the seam. Press the two edges of the seam together with your fingers for several seconds (follow the instructions) to secure the glue.
Step 5
Allow the glue to dry 24 hours before you vacuum or walk on the spot.