Always be on time, if you cannot, be let the Photographer know. Punctuality is very important."safety tip": If you are not taking anyone with you to the shoot, let someone know where you are and with whom. And be sure to tell the photographer that someone knows where you are.
 

Always go prepared : ie...clothing changes that you know will fit you. Don't always think that he/she will have everything that is needed for the shoot.
 

Always take your own make-up; even if he/she has told you there will be a make-up artist there. Always think of the could be's.
 

Get references, as many as you can. That would include other models and/or assignments that the photographer has had. Check and double check. And be sure that a legitimate photographer is doing the same with you. Never take anything for granted.
 

Get phone numbers and addresses if possible, if he/she is hesitant. You might want to rethink the shoot.
 

Make sure that you know exactly what the shoot consists of, and never feel pressured to do anything that you do not feel comfortable doing. If nothing else, go by your gut feeling.
 

Always take along enough "cash" for cab fare etc. In case the photographer cannot provide adequate transportation. Most will, but always be prepared for the "just in case".
 

Keep in mind that modeling is a business, not a personal venture. You need to be prepared to negotiate with prospective employers, regarding everything from pay to content. Don't just drop out of contact because you don't like what's offered - either negotiate or say, "Thanks, but no thanks." You never know, the employer you turn down could well have your dream job later - and if you treat him or her rudely or with disrespect, you'll likely miss out.
 

Don't ever do anything that you might be sorry for later. What you do today can affect your carreer later down the road. "If you pose for a photo that you cannot show your family and friends, and be proud of it, it wasn't worth doing". Mainly YOU should be proud of it.
 

If you have a verbal or signed agreement on traveling expenses etc. Make sure that it is followed up on. Written is sometimes the best.