Anytime you have a casting, go-see or actual shoot, make sure you don't leave the house without at least one contact number for someone that you'll be working with. As soon as you get the information about where the gig is taking place, write down the number or save it in your phone. Most of the time you'll receive your instructions for a modeling assignment via email--make sure there is a contact number of some kind that you can use in case something comes up: running late, get lost, get in an accident, can't make it, etc. If no such contact number is included in the email, reply back and ask for one. Regardless of what kind of shoot it is, there's bound to be a "go-to" person whose number everyone should have.
Agency represented models may be instructed to only contact the agency directly if something comes up. This is normal and if this is what you've been told, then follow what your agent tells you.
Having a contact number or asking for one will show the client that you are responsible and serious about working with them. Should anything go wrong and you are not able to contact anyone because you don't have a number available, guess who is going to look bad? You. Most clients have heard every story under the sun from models and even if your reasons are legit, they more than likely won't have the time to listen to why you weren't able to make it to the shoot on time or at all for that matter. In the end you take the blame and get labeled as "that model", even if it was something out of your control. You'd be surprised by how forgiving clients will be once they actually hear from you on the phone. No call - no shows should be avoided at all costs. So save yourself the trouble and make that extra effort to keep a list of contact numbers for all of the upcoming modeling assignments or castings you have to go to. If you happen to get email and Internet services through your phone, then you'll be ahead of the game.