Darning
Weave over a hole, thread by thread, until it's solid.
The stitch
Darning weaves new thread over a hole until the fabric is solid again — a warp and weft you build by hand.
What you need
tool darning mushroom or egg thread wool or cotton, matched weight base a few anchor stitches around the hole weave over-under, over-under, tight
How to start
Anchor a ring around the hole, lay the warp, then weave the weft through it. Pull snug, not tight, and the patch disappears.