for day to day driving, you should leave the bra off, most people put a bra on for long trips and take it off upon arrival.

(just for the record, the 12 year old in me is attempting to concoct a completely juvenile joke about this topic but is coming up completely empty.... )

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You have your way. I have my way. As for the right way, the correct way, and the only way, it does not exist.