My advice with cast iron? Never buy anything new, go to garage sales, estate sales and flea markets and find something at least 30 yrs old. Never wash with soap, but take a good steel wool (soapless) scrub to it to clean any obvious baked/caked on food particles.
Season it with flaxseed oil - the process for doing this is from Cooks Illustrated and their test kitchen showed that there was a significant improvement using flax oil, than bacon grease or other old stand-byes. It's an oven method and it's going to take a few cycles, heating and cooling down the pan reapplying the oil between sets. I followed this about 2 yrs ago, with my old inherited cast iron pans and it's close to non-stick now.
After that initial seasoning, never use any soaps/detergents or strong cleaning pads on it (I use a bamboo scrubber designed for use to clean woks without removing their non-stick patina. After any contact with water or cleaning dry it off on the stove top with heat, perhaps touching up any bare spots with flaxseed oil or bacon grease.