Come to the shoot with your hair cleaned, unstyled and dry.  The basis of your hairstylist will need to be able to work with your hair in its best possible form.  Remember to have your hair colored at least the day before, if not 2 days before the shoot to ensure it has the correct time to develop.
If you have extensions to add to your hair, have them washed and dried and colored the same as your hair, ready to give to the hair stylist.

If you are not naturally tanned, please ensure you have a tan the night before the shoot.
Allow plenty of time for the tan to develop overnight and after your morning shower, moisturise your tan to keep it looking great.  Even a moderately tanned model can appear washed out under photography lights.  Be sure to get a dark tan.

It goes without saying, but look after your body.
Ensure you drink a lot (no really, a lot) of water the day before the shoot.  This will help your skin and face in its natural appearance and also help remove any visible lines and dehydration marks.
Remember to moisturise your whole body.  Really lather up and keep your skin supple and healthy.

Get a big nights sleep.  Dont go out partying the night before and wear loose clothing to bed.
Allow your body to soak up all that moisturiser, and water drunk the day before and allow you to get rest.  Photoshoots are typically strenuous and place a strain on your body holding poses and tightening muscles for a period of time. The more energy you can bring to a shoot the better it will be on the day.

Get dressed in loose clothes.  Try not wear anything that will leave unintended any marks on your body.  Wear comfortable shoes and stay warm.
Be sure to have your hair out, and not done ready for your stylist.
Have minimal makeup on ready for your makeup artist.  If you have a particular product you would like to use, be sure to bring it.
Remember the goal isnt to turn up looking a million bucks, but to transform into this through the shoot.

With all the chaos that is around doing a photoshoot remember to breathe and take your time.  Ensure you are prepared and know where we are meeting and aim to get here early.  Everyone has schedules that they are trying to work around and arriving late and having to rush the shoot, the stylist, the makeup artist or the hair stylist does not help.
But most of all, if you have any questions, don’t hesitate to ask.  Be sure to reach out if you are unclear or want to change anything.  Things happen and situations change, the more notice, or questions had the more prepared everyone can be.

Setup a mood board, share images with your photographer, stylist, makeup artist and hair stylist on what you are looking at for inspiration.  A great resource is Pintrest where images are shared, and collated all around the world.  Be sure to set up a Pintrest account and work through concepts and designs.
Here are some every building boards i have and use:

Fashion and Beauty
Glamour
Natural Light
Escort Style
Rooftop
Studio Style