The less is more rule applies to many things but I think its especially important in photography.
If someone else is shooting you may not have a lot of say on how the image will look but do make sure there are some simple shots there - clean, easy, things that can be used in your portfolio and books. Don't just take reams of quirky photos - people want to see you looking fresh and simple too.
If taking the photo yourself, then remember, when framing and composing thephotograph, we want to create something interesting for the eye to see but at the same time avoid excessive distractions. Normally, one main focal point or area is enough especially if you are showing yourself off as a model!