Put on your respirator mask and safety goggles before opening the batts of insulation. These will protect you from the fiberglass particles in the insulation.
Open the packages of batts insulation by cutting gently through the plastic packaging lengthwise, using the utility knife.
Lay the batt on a hard, flat surface, such as a concrete floor. Press the scrap wood down to compress the insulation and then cut the batt to the sizes needed to cover the square footage of your porch's walls. Use short strokes with the utility knife.
Push the batts into the cavity between the frame and drywall, so that it sits all the way inside. Then fluff the batts forward to fill the space.
Staple the batts into place on the edges of the framing boards. Do not stretch the batts too tightly to staple.