Step 1. Segregate the gluten! Designate a separate area for gluten containing food. My husband has the small counter space on the other side of the stove and the drawer beneath it for his snack food. I have a drawer on the my side of the kitchen for gluten free snacks. He prepares glutenous food only on his designated counter space.
Step 2. Bowls and dishes. Things like plastic ware and Teflon can hold onto gluten and release it back into the next food that's served from it. If you stored a bunch of bread in your Tupperware, washed it, and then thought it would be a good place to store your gluten free cereal, think again. Plastic ware, like Teflon, is porous and scratches you can't see can contaminate your food. Be safe, get separate plastic ware for your gluten free food. Wash and store plastic ware separately from gluten containing dishes. Use stainless steel cookware and glass or ceramic dishes.
Step 3. No plastic spatulas unless you can absolutely keep them separate from all gluten. Be sure they are never used for cooking or stirring anything containing gluten. The rule for plastic ware extends to utensils because they are just as porous and open to scratches that can catch gluten and contaminate the food.
Step 5. Get a new toaster! This was one of the last things I ever did and should have been one of the first. Putting a piece of glutenous bread into a toaster contaminates it. I got a pretty red toaster for my side of the kitchen and gave the old one to the hubby side of the kitchen. One last thing on the toaster? If you have overnight guests hide your Gluten Free toaster so they don't put gluten in it before you get up in the morning! This happened to me and I had to get a new toaster. It's impossible to clean gluten out of a toaster.
Those are the 5 big ones. I'm sure I'll think of more. I've been GF (gluten free) for 10 years so I'm sure there are things I'm doing but not realizing it. If there's anything I missed please feel free to leave a comment.
Be happy, be gluten free! I hope this helps.