Looking for some experienced advice!

I have suggested to all parents that when they are ready to potty train they start on a friday after daycare.. take the whole weekend to practice and IF it goes well then I will continue the training during the week... what does the weekend going well look like?
- Child is telling you "they need to go potty" before they go potty on a regular basis
-Child is confidently using the potty with ease

so what else should I be asking/preparing parents with?
Do you ask parents to send their children in pull ups for a certain amount of time or do you allow them to come in underwear right from the start?

When I trained my own children I went straight to undies as I feel it does encourage quicker training - but lets face it there were lots of puddles on the floor.. not sure I want to deal with that in a daycare setting??

any advice is welcome! thank you!