Out of the window of course. Where else would you want?

It goes straight to earth again and sometimes if someone is lucky it will nourish their hair

Like general_kitten@sopuli.xyz said, into bottles and recycle if you can. I’ve also had good results with:

• paper towels - this can take a lot, so reserve those mostly clean ones in a bag/bucket for later use
• sawdust in a small bucket that I keep in the garage - dump it into a trash bag and throw out once saturated
• Japanese cooking oil solidifier - this stuff is incredible and turns oil into a paste that is easier to throw out

somewhere you don’t like’s drains.

into bottles and then put bottles into regular trash, there are also companies that recycle oil into biodiesel but i dont think they take regular consumer oil unfortunately

Contact your city or locality, many will take oil at a recycling center and send it on its way. Anything you can’t funnel into a container for recycling, scrape into the trash.

Burn it.