preparing the machine
1. needle: left or right, or both left and right
2. stitch type: three—thread overlock or four-thread overlock
3. stitch length: 3-5 mm
4. differential feed lever: gathering position
5. upper knife: working position
sewing
1. place two layers of fabric on machine with separator plate (a) in between the upper and lower fabrics.
2. sew 2-3 stitches.
3. hold and lightly guide upper and lower fabrics separately while sewing.