This DIY snuggle sack requires minimal sewing skills, and is easily accomplished as a first-sewing-project. It is far faster with machine sewing, but may be handsewn with patience. Construction time with a sewing machine is approximately 10-30 minutes depending on skill level. The final product is fully-lined and reversable with no exposed seams.
The hedgehog used as a scale-creature and demo in these photos is approximately the dimensions of a very small adult hedgehog (and half the size of the hedgehog who uses these sacks).
Step 1: Cut fabric.
Cut two equal-sized rectangles. The final sack will have the same width as the rectangles (minus seam allowances), and half the length of the rectangles (minus seam allowances).
Cut two equal-sized rectangles.
Flannel, cotton, fleece, corduroy, or other tight-woven strong fabrics are all good to avoid catching tiny toes or shredding during attempted burrowing. Special-purpose sacks may be constructed using a layer of waterproof fabric to protect against accidents with baby creatures, or microfleece liners for post-bath cuddles while drying off.
If you care a lot about final size, you can pre-wash fabric to shrink it. Otherwise, expect it to shrink during the first laundry cycle. Pre-washing is strongly recommended if you are using different fabric types, as otherwise they may shrink unevenly.
Depending on the size and width of fabrics I have available, I usually aim for 6-8" wide x 12-16" long for my 9"-long hedgehog who likes to nap curled up in a ball.