Too much oil when seasoning cast iron can lead to a sticky and splotchy cast iron. I use a very simple approach when I use oil to season my cast iron skillet. The oil that I prefer to use when seasoning cast iron is bacon grease. I love the slick not-stick cooking surface my cast ironware has when I cook. Plus, bacon grease has been used for hundreds of years by our ancestors.
Every morning when I cook bacon for my family, I reserve the bacon drippings. I pour the drippings through a strainer to catch the bacon bits. The filtered grease is then poured into an egg carton compartments. After the grease has been poured out, place the egg carton in the freezer to harden. After a few hours, you can pop out the frozen lard and place in a plastic bowl in the fridge.
When I'm needing to season my cast iron, I take one of the round pieces of bacon fat and place it on a warm skillet. Rub the grease into the skillet with a microfiber towel or shop towels (Amazon has some pretty amazing prices on these two items).
Each capsule of oil provides just enough oil to season your cast iron skillet. If you didn't use the full capsule, you can place it back into the egg carton.
Seasoning cast iron is not a very complicated process. Many sites do not provide enough information about the seasoning process. CLICK HERE for information about the seasoning process I use. This process has always been guaranteed to work and provides enough layers to make a nice non-stick surface.