To choose the ideal patch fabric for performance and aesthetics, take the following aspects into consideration and match them to the garment:

Weave Structure - Whether the fabric is woven or knit.

Fiber Content - The fiber that the fabric is made of (cotton, nylon, etc). This will likely be written somewhere on the garment tag.

Weight - How thick and rigid the fabric feels.

Stretch - Whether the fabric stretches horizontally, vertically, or both.

Color - Matching color is up to personal discretion but often a slightly darker fabric will look less obvious that a slightly lighter fabric.

Preference - A preference for a contrasting patch for a more visible repair.