Step 3: the magnet
Now you have a sugru base layer on your tea towel use the other sixth of the pack to fully encase the magnet.
sugru bonds to sugru extremely well, but to get the best bond make a point on one side of the magnet to push onto the tea towel. The point will squash the sugru outwards from underneath the magnet giving you the best possible bond.
TIP: Once the magnet is fixed to the tea towel, blend the edges around the magnet to the base layer of sugru. This will make your hack much more robust. If you don't blend the edges, the magnet can tear off over time.