Back to front means with the rear part facing forward. His jumper was back to front, do it back to front.
It is not the same as inside out, and doing both at once is entirely possible. Figuratively it means done in the wrong order, which is the commoner adult use.
1phraseback to frontWith the rear part facing forward.
“He had his shirt on back to front for the whole morning.”
back to front is a phrase.
Practised in Directions & Position