What is a "tailor’s ham" please? Never heard?
Correct pressing is very important when sewing, and such a pressing pillow be of great help, for example to iron darts softly. By pressing over the pillow, the fabric can be brought more into shape.
You can easily sew such a tailor’s ham yourself, a few scraps of fabric are enough for that.
I have prepared a pattern for the tailor’s ham. Download it and then cut out the shape once from a smooth and once from a somewhat rough material. My pillow is made of flannel and an old duvet cover. Synthetic fabrics don't usually tolerate excessive heat, so it's best to use cotton.
The two fabrics are then simply sewn together, leaving about 5cm open. The pillow is then turned through this opening.
Tailor's hams are traditionally filled with wood shavings. You can also use scraps of fabric. The filling should be stuffed tight, there is a lot going on.
When the pillow is filled, close the opening with a mattress stitch. A stitch a few millimeters long on one side always follows a corresponding stitch on the opposite side. This seam is later almost invisible.
Your tailor's ham is ready!