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.
Step 2: Fold Fabric.
Fold the rectangles in half, right sides together. (Right side = the side you eventually want to show. For printed fabric, the patterned side is the right side.)
The fold will be the bottom of the sack, and the opposite open end will be the top-entry of the sack.
Stack the two rectangles on top of each other, right sides together.
Step 3: Sew Sides
Sew the sides together. My hedgehog likes to burrow inside his sack, so I make sure to sew extra-strong (small stitches, double-back) on the sides closest to the fold.
Sew the rectangles together along the two short sides and one long side. Leave one long side open.
Optional: Tie the thread ends to secure them, then clip them short.
Step 4: Invert One Bag.
Invert one bag (doesn't matter which) so it is right-side out. For fabric without a print, the seam is on the wrong side and hidden on the right side.
Do a small waiting-dance for the main variant sewers to catch up with your awesomeness.
Optional: iron it flat.
Step 5: Stack the Bags.
Stack the two bags with right-sides together, so that seams are on the outside and inside of the new lined bag.
Rearrange how the bag is folded, so side-seams are aligned and like-fabrics are stacked on top of each other.
Note for experienced sewers:
If you are comfortable using double-folded bias tape, for the main variant you can instead stack the two bags right-side out, and finished the top side with bias tape (pictured with microfleece fabric).
Step 6: Sew Top Edge.
Sew the top edge of the bags together, leaving a small opening. The opening needs to be big enough to pull fabric through -- a few inches is usually good.
Sew the top edge of the bag together, leaving a small opening. This will be the weakest point of the bag; I usually keep it close to the side seams on the outside-fabric.
Optional: leave one long thread (for later hand-sewing)
Step 7: Pull Fabric Through.
Pull the fabric through the opening left in the top seam. Finish pulling the fabric through the opening in the top seam. At this point, all the right sides are exposed (prints, no seams).
Pull the fabric through the opening left in the top seam.
Optional: Tuck and fold until the fabric looks like a bag.
Step 8: Hand Sew Opening Closed.
Hand-sew the last opening closed. As this is the weakest point in the bag, keep an eye on it over time to make sure it doesn't unravel.
Hand-sew the last opening closed.