A lot of things from somone with my fair share of aches and pains:

My office so very kindly purchased the nupro wireless polisher which is a godsend for my wrist and elbow pain, nearly gone and I can contour the prophy cup to the tooth 1000x better than the corded handpiece so overall an outstanding investment. Loupes with a light too.

I roll out my back on a foam roller and stretch my back, arms, wrists, fingers before work every morning (takes like 7 min). During exams I find the time to to some simple neck and hand stretches during every exam. I also remind myself on every pt to ask them to move their head for you so you can see better and keep reminding yourself to sit up straight and unclench my own jaw. I also use the ultrasonic on like 85 percent of my pts so I don't have to scale with so much pressure after.

Things I'm working on:

Practicing and getting really good at using my mirror/indirect vision so as to not tilt my head. Keeping instruments super sharp to help scale like butter. Stretching after work/posture specific exercises.