You get a radio-controlled hotshoe. One piece mounts to your camera hotshoe, the other to your flash unit. Then have your assistant bounce the flash off the wall or ceiling near your subjects. The flash is synchronized to your shutter. If you don't have an assistant, you can mount the flash to a tripod.
http://smile.amazon.com/gp/product/B002W2DPYC
However, the advice by /u/JSAlmonte is probably more useful than mine -- bouncing the flash is more important than having it off-camera.