Cut the carpet into 4-by-4-foot squares that you can hold above your head while working, using a razor knife.
Climb the ladder and hold a corner of the carpeting to a corner of the wall.
Staple the carpet corner in place and then staple the edges. Use plenty of staples throughout the carpet to prevent sagging.
Place seaming tape on the edges of each carpeting square.
Heat the seaming iron and press it on the seaming tape for 30 seconds.
Press the carpet edges down firmly on the seaming tape.
Repeat the process to attain the desired coverage.