Crossword puzzle clue "replacement for those left out"

Replacement for those left out

Wrap right over left, tuck right underneath, pull, pinch right in a loop, wrap left around, push left through hole to create loop, pull loops

"Those people who think they know everything are a great annoyance to those of us who do" quipster

Next to these dog treats, or those over there, or those...?

Dish in a lab used for examining cultures (those are science terms for those who haven't studied science)

Schooling for those on the left?

Slogan for some of those on the left, and, if read a different way, an explanation of this puzzle's theme

Up, Up, Down, Down, Left, Right, Left, Right, B, A, Start; etc.