Here are simple instructions for adding images such as letters to linen towels.
Fourth of July decorating

For our festive buffet, we decorated linen tea towels with letters.

To make your own, place a toner-based image (use a laser printer or a toner photocopier) face down on a linen towel. Secure the image with masking tape. Remember that type needs to be printed backwards so it reads correctly. Using a brush, spread Citra Solv cleaner over the back of the paper. You don't need very much. Burnish the back of the image with a spoon. You will need to put some muscle into it. The harder you press down, the darker the image. Lift a corner of the paper to see if the image is transferring and remove the paper once satisfied.