Sleeping bags get dirty, just like the sheets on our beds get dirty after use. However, it's rather difficult and time consuming to wash sleeping bags. To solve this problem, you can use a sleeping bag liner. Sleeping bag liners are easy to clean, comfortable, and they can be used as a lightweight alternative to thick sleeping bags. With basic sewing skills, you can make your own sleeping bag liner and save a lot of money.
Cut a piece of silk that is 4 yards long and 1 yard wide. Fold the fabric piece in half, horizontally.
Sew up the left side perpendicular to the fold. Fold over the remaining raw edges about 1 inch and hem, tucking the raw edge under as you sew.
Cut the bottom corners off of the sleeping bag liner so that the bottom of the liner forms a circular shape. Sew up these edges.
Sew on a zipper or Velcro to the right side perpendicular to the fold and turn the sleeping bag liner right side out.
Cut two pieces of elastic that are each 12 inches long. Sew each piece of elastic in a loop to either bottom corner of the sleeping bag liner so that the liner is easy to fold up.
For a slightly heavier liner, use lightweight fleece. You may extend the bottom layer about 12 inches at the top to make room for a pillow to rest on the liner. Make the sleeping bag liner longer for anyone over 6 feet.