How do i drain old engine coolant? no idea where

The textbook method is to remove the drain plug on the bottom of the radiator.

Most drain plug is make of inexpensive nylon/plastic and it may fall apart while you turn it.

The professional method is to loosen the lower radiator clamp and drop to lower radiator hose.

Drain the coolant onto a large drain pan and recycle the coolant

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if your under your car look at the bottom right side of the radiator( could be left side, not likely though) its white and plastic, kinda resembles a wing nut, unscrew it a little and...... DRAINAGE!!! oh you can also unhook the lowest tube in your overflow tank if u want to drain that aswell