Measure the length of the floor where the carpet and tile meet. For example, if the area is a doorway, measure just the doorway width. Write the measurement down on a piece of paper. You need this measurement to know how long of a transition strip you need.
Get the transition strip appropriate for creating a smooth transition between sections of flooring that are an unequal height. These strips are sloped and are sometimes called reducer strips.
Cut the transition strip to the appropriate length, if necessary. Wear safety glasses and work gloves to protect your eyes and hands as you cut the strip. Use a sharp saw.
Put the transition strip on the area where the carpet meets the tile to double check that it fits correctly over the carpet and tile. Drill the pilot holes and screw the piece into place or use the factory recommended adhesive to glue it into place -- use the process recommended by the transition strip brand.