Shooting swimwear (or anything for that matter) in the bright afternoon sun can be brutal. It can be ok under some circumstances because you kind of expect to see really bright highlights and dramatic shadows on a sunny day at the beach. Notice that to get a decent exposure on her face, the sunny side of her hair and legs are completely overexposed and blown out. Her eyes remain underexposed, and a reflector still needs to be used to fill in her eye sockets. Shooting in the harsh sun is brutal I tell you! Just brutal!
If you’re trying to get any kind of beauty shot with even exposure, you need to control that sun. One option is to find shade under a big beach umbrella! I moved her under one but you can see the ugly outline of the umbrella. I later moved the model to have her entirely in shade and not have the distracting difference between sun and shade here, but I wanted to show you the difference between the sun and shade.
The ideal solution is to wait for the “golden hour” which is roughly the hour before sunset (or the hour after sunrise) (but hating mornings, I see that morning golden hour as little as possible thank you!). During the golden hour, the sun is low on the horizon and the light has to go through much more junk in the atmosphere which softens the light and turns it into magnificently soft and beautiful color.
The model above was not able to stay that late, but here’s one who was able to. Look at the beautiful, soft light, and check how calm the water is, too: