Having spent a decade and a half on shop floors, and in home improvement retail, I can tell you what worked for me over those years, and what I have implemented in my own shop...
#1, and most important. High quality footwear. I specifically wear Hi Tech full leather upper hikers, and Thorlo hiking socks, year round. They wick moisutre away from my feet, keep me warm without frying me no matter the climate.
#2. Anti Fatigue mats where you will be standing for long periods. In the home improvement centers, we used them at each of the cutting stations.
#3. Get off your feet when and where you can. Invest in some good quality shop stools, or build some. I have a pair of stools from Woodcraft. Not the best, but they are a place to put my backside and get the weight off of my knees for a while.... I like to use these especially when I am at the work bench, or band saw. Not so much for the table saw / lathe etc.. However even though OneWay claims to have the only "sit down lathe" out there. I have been known to sit at a stool while turning. Not sure that is a good idea, not sure it is a bad one either...