Most surefire way I know is preheat your oven to 450, put a tiny but of canola, rapeseed, or another neutral oil on it, wipe off as much as you can with a paper towel and toss it in the oven for half an hour, the nrepeat 3 or 4 times. When I say remove as much oil as much as you can, I mean the towel should come away juat about dry. Then to cook with it, let it get hot first, add some form of fat, butter, oil, bacon grease, etc. and then add your food. Waiting for it to get hot first is the key.