I was recently asked how I achieve this, so here are a few tips;
Technical: I shoot wide open using the lowest aperture my lens will allow (usually f 1.2) and I often shoot in Aperture Priority mode (AV) and underexpose by a stop.
Composition: Compose your shot with the sun directly behind your subject. I love capturing the sun's reflections bouncing off different surfaces, flare into the lens, and different textures and contrast it produces. Also the way the sun back lights and interacts with my subject adds extra magic!
I'd love to see any shots you take. Happy shooting!