Ok, so I'm no photographer...

but through this "naked project" of mine I have encountered a few very new photographers who have just purchased their 1st real camera and are anxious to have DNA, Women and other such model agencies banging on their door in "East" Williamsburg.

Often these guys share with me their woeful tales of "having" to shoot "ugly" models.

I have been a professional fashion stylist for 8 years I have also art-directed and produced shoots. Thus from experiences, I feel I can offer my humble opinion on the subject:

When seeing a photo of a model or her comp card, before choosing her make sure she you have some feeling of inspiration from her image, after which you should meet her in person (a go-see) to make sure her photos are representative of who she is (like, she hasnt aged by a decade or gained 20lb, etc). Also and very importantly, you must watch for a good rapport with her or try an establish one if she's difficult or shy...or foreigh who speaks 3 English words. Also at the meet go through every image in her portfolio, look at the natural unretouched ones carefully, study why those photos worked, what is his/her best angle, feature, most natural way of posing etc. Use this research as a way to save yourself time so you don't have to reinvent the wheel every time you shoot someone new, have ideas of how you will shoot them before you start.
When it comes to "testing" where you are sent someone new from an agency (or no agency) who is too new to have any pics you can study and or you notice that during the shoot the pics are coming out just terrible, try taking a break and investing a good hour talking with her, having her relax, drinking tea or wine (if she's of age) or whatever- try to see what her lover would see in her, take snapshots as you speak...
This works very well for character portraits especially.
Don't have her do weird fashion poses if its not her, use her style. As a photographer, your camera is the eye to her inner beauty and it is your job to bring it out. Of course its easier and GREAT if in comes a 6 foot photogenic beauty who knows how to move and emote and has a great personality and whose skin you barely have to touch in photoshop, but on the flip where's the challenge in that? = )

The above Polaroids were taken by Frank of www.frankaugust.com, as I danced to gypsy music!
Frank is so adapt at drawing out (the best of) your characater that it's incredibly easy and a high to pose for this gentleman of a photographer. The site I linked is his personal projects work, but he is also a well seasoned photographer with a polished editorial and commercial portfolio under his belt. But what a dynamic individual! Aside his charm and easygoing nature, there is a serenity yet wildness about him (as if he were a 60 year old sage and at the same time a 12 year old boy). Bigg kiss to Frank, xoxo!