Snake stitch is a very simple edging or outline stitch for hand embroidery.
This stitch is also known as: snake stitch, rope stitch or cordonnet stitch.
Sew a row of running stitch. Use a blunt needle and bring a thread of a different colour up next to the first stitch.
Slide a needle from right to left under the next stitch, remaining on top of the fabric and pull through. Continue snaking the thread to the end of the running stitch. Don’t pull too tight.
The thread goes from right to left and from left to right underneath the running stitch until you get to the end of the row.
Then you take the needle back through to the back of the fabric and cast off and there you have your snake stitch.