Plug in the carpet seaming iron. Allow it to heat for a few minutes while you prepare the carpet.
Trim the carpet edges with scissors to ensure a snug fit between the two carpet pieces.
Place carpet tape beneath the two carpet pieces, adhesive side up. Align the tape so each carpet piece covers one-half of the tape.
Set the carpet iron on the tape. Move the iron slowly along the seam, heating the glue and allowing it to melt into the backside of the carpet.
Place a heavy object over the carpet seam. This ensures the carpet stays in close contact with the carpet tape as the glue dries and hardens.