Indeed common sense is called for as is basic safety precautions.
I've been mixing my own PMK pyro for a number of years and more recently Pyrocat-HD. I take the precaution of wearing nitrile gloves (little more durable then standard latex). It is also considered prudent to wear eye protection and a dust mask when mixing toxic dry powders, in case they become airborne.
Take your time when mixing chemicals, be as accurate as is humanly possible and also stand up while doing so, never sit down. As a laboratory technician for 40 years, sitting down while mixing chemicals was considered a cardinal sin. If I saw any of my subordinates doing so I certainly pointed this out to them.
Sorry for the mini-lecture but old habits die hard