For a few days, I used just grape seed oil. I was feeling oily on about the 3rd day, so I added some castrol oil. This is all mixed in the original gso plastic bottle it came in, with about a quarter sized opening.
I do the cleanse in the shower. I take off the lid, set it down, and pour a bit in my hand. Since I don't want the oil to run out of my hand, I just wait and put the lid back on until after the cleanse is done.
Last night, I was rubbing in the oil, when DH decided he was going to "sneak" in the shower with me.
As he got in, he kicked the bottle over, and oil went all over the tub.
Oil on the floor of a tub is NOT safe. Not safe at all.