If your shoot is outside, be mindful of the wind and the chaos it might create with your hair. Consider taking along a brush and some hairspray to control possible flyaways.
If the weather is bad and you don’t have a plan B for shooting inside, be sure to get in contact with your photographer to discuss rescheduling the shoot.
The most important thing is to be comfortable, as your state of being will come through in the shot. You might even consider inviting people you trust and that bring out the best in you along along for the shoot to make the experience fun and bring out your best smiles.