Safety and common sense

As a photographer you have to keep in mind that when doing modeling photo shoots with people you get many types, more so when doing TFP (Trade for Pictures)

You get the ones that will never be "Professional" they just want pictures to show off on social media.  You also find ones that would make it in different areas of modeling, are very photogenic and yet they shy away from going professional.  From portrait photography to head shots keep yourself safe.
The ones you do have to watch out for are the ones who will just criticize and back bite you after the shoot.  There are social media groups who do not help aspiring models or just those looking into modeling get anywhere.  They teach them bad posing techniques and lead them down paths that are dead ends.  They recommend photographers who are immoral  trying to get models to sleep with them or just take nude pictures.  If you try and tell the group what is right and who is doing the shady work they ostracize you and try and tear you down and discredit you.  Run from these groups.  Run from the drama. Being associated with these types of people and groups can reduce your chance at getting real work or working with photographers who can get you where you want to go as a model.

If you have worked with a photographer that has made you uncomfortable, leave, even before the shoot is over.  After the session go to their business page and review it, give the reason why you liked them or did not like them.  This will help others avoid the bad ones and go to the better ones.  Don't review them with fake reviews, only if you have had first hand experience with them on a photo shoot.
Always go to the photo session with someone.  This will help keep a shifty photographer on task hopefully, if not you will also have a witness.  Even if a photographer promises you that you will be in a magazine don't feel pressured to remove clothing.  Many have online magazines that they will post your pictures in, stand your ground.  Many of these online magazines have followings under 1000 who are mainly people who have been posted in them. I could start one tomorrow and find a larger audience.  Many jobs you get as a spokes model have restrictions on how you look when doing these jobs.  So be careful before you post yourself nude. Unless you are already famous.

When doing a release for the photographer make sure you have something like this "In consideration of the payment of digital images and deferred payment of 10% or $100.00 of the commercial
sale of images." This gets you paid if your image is sold commercially to another company.  In the release contract it should say how many pictures you will get digitally and a time frame until you get them.  Things happen so be a bit flexible, most photographers need to make money so that will be priority over finishing your pictures.  After a month just remind them.  The photographer will retain the rights to the pictures and the use, unless you are famous and they agree to limit their rights, the photographer will always keep the rights.  Money helps if you really want full use of them as a model, then its not TFP any more.
Safety is your priority on a photography session.  Always let people know where you are going and who you are meeting up with.  Even if you have worked with them before.  Bringing a friend or two is best.  Some areas where photo shoots are done there are bad people out there who would try and rob you or worse, more people with you the less likely that will happen.