RK9 is preferred: https://rk9.gg/decklist/index
You may also print a decklist here: https://www.pokemon.com/static-assets/content-assets/cms2/pdf/play-pokemon/rules/play-pokemon-deck-list-85x11-par.pdf
Ordering your deck in the same order as your deck list for checks is helpful but not required.
Top 8 cut participants will all have a deck check after cut, even if it’s already been checked.