I'm assuming you're at your store at this hour. All I would recommend is getting plenty of sleep and maybe a nap before your shift. Bring music, probably not for this overnight
since you're going to be training. Coffee and energy drinks help too.
As for presentation tips, make sure you look at the planogram before you start setting. Make sure you have all the necessary fixtures, backer paper, tools, labels, and signs. This will save you trips to the fixture room and a great deal of time. When you're training make sure you follow along with your trainer and ask questions.
Before you demerchandise an aisle make sure the pog isn't carry forward! Don't throw away any signs that are carry forward, if you don't know then don't throw them away.
Beware of papercuts from back paper, seriously.