A lot of people are talking about better ergonomics, which is great and helpful for preventing symptoms. But for me, what helped most to reverse my symptoms was performing finger extension exercises throughout the day.

Mouse clicking is all finger flexion so you need to balance that out by working the opposite muscles. Finger extension stretches (lifting one finger at a time off a table; stretches the flexor muscles), finger tendon glide, and finger spreads (spreading fingers apart with a resistance band; strengthens extensor muscles; my fav) have all been incredibly helpful in managing symptoms.

Ball squeezes on the other hand aggravate my symptoms because they work the same muscles and motions that clicking does. So don’t do those.

Could also try a parasol or wide brimed hat to keep the sun off.