If you were sneaking away with your s/o for a short trip, what all would you have to remember to do?

Assume, for some reason that you need to go on a trip with your s/o and you don’t want your parents/friends/others to know about it. What all would you have to remember to do in terms of packing, making reservations and planning other such details, while ensuring that your cover isn’t blown ?

Also, if this were going to be your first trip together, a list of Dos and Don’ts would also be helpful :)