WE had some professional photos done for Claire recently and the photographer suggested simple looking clothing, with not too many colours so the clothing doesnt end up being the main thing in the picture. We ended up dressing Claire in a little pink flowy dress with small flowers on it. Its pale pink and it was good because it didnt take the eye away from Claire. We also brought another outfit for her - little dark jeans and a dark red and pink top/dress thing. The top/dress was like a long top or short dress and without her pants on it shows off her nappy. Anyway, it all worked well for the pictures.

If youre having the pictures outdoors and want her nappy to be shown, maybe try a little dress if you have one? I suppose it depends on what style of picture you want.