which foot the shoe is on

act one's age, not one's shoe size

Synonym of act one's age (“to behave in a mature manner; to avoid being childish”).

as ever trod shoe-leather

As ever existed or lived.

every which where

everywhere

foot the bill

To pay for something.

foot voting

Expressing one's preferences through one's actions, by voluntarily participating in or withdrawing from an activity, group, or process; especially, physical migration to leave a situation one does not like, or to move to a situation one regards as more beneficial.

get one's foot in the door

To initiate contact or a relationship; to gain access, especially to an entry-level job.

have one foot on a banana peel

To be in an unstable situation with a high risk of sudden negative change, facing difficulty, or appearing foolish.

heavy foot

A habit of driving fast.