Here are the steps to make a swaddle blanket:
1. Find your favorite knit fabric for your swaddle blanket. There are so many beautiful prints of fabric. The best fabric to use for a swaddle blanket is a stretchy knit.
2. Square it up. Hold the material up with selvage edges together and shift the material until it hangs straight.
3. Finishing. Now it’s time to finish the edges. You can use a serger or a zigzag stitch on your sewing machine to finish the edges of your swaddle blanket.
Here is a tutorial I found that has pictures and more detailed instructions on how to make a swaddle blanket:
