Things You'll Need
When carpeting your home, including the stairs, you should take proper precautions to make sure the carpet actually stays on the steps when you nail it down and doesn't cause you or your family members to trip by lifting up in certain areas. You will save money by learning how to carpet and nail it down properly on your own, rather than hiring a carpet installation professional to do it for you.
Begin at the bottom of the stairs, and lay a piece of tackless strip at the top and bottom of the stair set and on the bottom of the tread and back of the rise for each step. Center each strip on the step, and make it approximately 1 inch shorter than the width.
Drive nails into the corners of each tackless strip to secure it to the floor. Use carpet nails to ensure that they're the proper length and thickness.
Cut the carpet padding to place on the tack strips. It should be approximately 3 inches longer than the flat portion of your stair so it wraps under the lip of the stair, and it must be 1/4 inch shorter than the size of your carpet runner so it adequately pads without sticking out on the edges. Use the hammer to nail the padding to the tackless strip on the flat part of the stair, and then wrap the excess padding under the lip of the stair and nail it into the strip on the back of the step under the one you're working with.
Place the carpet on the steps, and use a knee kicker to press it tightly where the rise and tread meet on the stairs. Install nails approximately 3 inches apart where the two meet. When the carpet reaches the top of the stairs, nail it to the strip and padding to complete the installation.
Have an assistant help with holding the pieces tightly in place while you nail them.