Measure your stairs to see how much material you will need. Be sure to measure the depth and the width of the tread and the height of the riser. Then count the overall number of steps, multiplying it with the tread depth and riser height, to calculate the length of carpeting needed. However, you will need to add about15 percent of the material, because of the nose of the tread, possible mistakes and corners along the staircase.
Cut the carpet into the needed width with a sharp utility knife and a metal ruler. Note that it is much better and easier to order the needed width directly from the store. However, the best solution is simply to choose a carpet of the needed width.
Attach tackless strips in the corner of each step, using a hammer and nails. Use metal snips to cut the strips to size, approximately 2 inches shorter than the width of the carpet.
Attach a piece of carpet pad to each step, from the tackless strip to the nose of the thread. If your staircase doesn't have a turn with all straight steps, but instead has steps with uneven thread width, adjust the carpet pad to each of the steps nevertheless. Use a heavy-duty stapler to attach the carpet pad base to your stairs.
Lay the runner to the first step, making sure the carpet adheres to the step properly and completely. Use latex carpet glue first and then a heavy-duty stapler. Remember to use long staples so they penetrate through the step itself and not just the carpet pad.
Continue with carpeting the stairs, using latex glue and staples to attach it firmly to the steps. If you have winders, cut the carpet to make special, custom shapes to install. Make the joint between two carpet pieces in the corner where the riser and tread meet, in order to get a seamless transition.
Secure the carpet to the corner between the rise and tread with a special carpet tool and a rubber mallet. Instead of a carpet tool, you can use a metal scraper tool.