Put on your work gloves to protect your hands against the sharp tack strips and staples.
Start at the bottom stair and use the needle-nose pliers to grab a bottom corner of the carpet and pull up. This will separate it from the surface and pull it away from the tack strip.
Grab the loose piece of carpet with your hands and pull up on it. If you are having trouble dislodging it from the tack strip, wiggle the piece of carpet to help free it. Continue pulling up on the carpet up the stairs until that section of carpet is removed.
Work your way up the stairs until all of the carpet is removed.
Pull up any staples in the subfloor by gripping them with the needle-nose pliers and then twisting the pliers.
Remove the tack strip attached to the subfloor by wedging a pry bar between the bottom of the tack strip and the sub-floor. Hit the pry bar with the hammer to help get it completely under the tack strip, then pull pull up on the pry bar to dislodge the tack strip.
Work your way along each step until all of the tack strip has been removed.
Pull up any nails remaining in the subfloor with the claw end of the hammer after all of the tack strip has been removed.