Outdoors, a flash, a powerful one, will often make good images into great images. Because you can make the background darker:

Here’s how we took a shot at a creative light workshop last year:

Which leads to this shot:

As always:

1. Get the background right first; remember to keep the shutter speed below your maximum flash sync speed (like 1/250th sec).
2. Then add flash.
3. Set the flash power to the aperture you have gotten to in step 1.

Really simple, no? Provided that you have a powerful enough flash to overpower the sun, of course.