Hmm...
Let's start with my favorite - gardening. I wear a mask, make sure the soil is moist to limit airborne dust and try to wear long sleeves/pants (not perfect at that yet, but have gotten some super lightweight wicking clothes) - and I have learned to shower and wash the clothes afterwards. I stay out of the garden when digging is going on or mulch is being laid.
In one home, we have HEPA on the HVAC, but I like open windows so we also have portable units. In our tiny house we have a portable HEPA system & clean the a/c filter.
In one home we have a whole house water filter (it's a pain with the tiny pores so has a prefilter on it.) The water has tested twice negative for NTM, so we might quit. In the other house we have a well - no NTM, but use a filter for tast & I change it every 2 months. I truly don't worry much about it as I have no GERD, though I do drink bottled spring water when we travel.

We have a hot tub in our tiny house community which I completely avoid. But I do use the community salt water swimming pool (keeping my face out of the water.)

One thing I seldom see mentioned, but that we do, is keep our reuseable water vessels - pitchers, glasses, mugs & covers, sippers, etc - scrupulously clean - soaked then washed daily in hot soapy water & scrubbed vigorously with bottle brushes of various sizes to keep any biofilm from forming. At the big house, I scrub before putting in the dishwasher.

I would like to hear others here can share their own strategies, but this is what works for me.
Sue