Uh, I guess the only important thing is knowing the available romance options?
Judy - Lesbian
Panam - Straight
River - Straight
Kerry - Gay
Keep that in mind while creating your character.
Also, the origin story you choose doesn't make a huge difference, so feel free to go with whichever you like.
Other than that, I guess just keep extra saves? I very much enjoyed getting all the endings, and if you have a save at the point of no return you can get them all in one playthrough.
All the stars in the sky are waiting for you.