While on transit, I secure it with double enders to harness D-rings, usually one on chest and another to crotch, so camera/housing is in line and reduces drag
When I use the camera, I use a surfer's leash with a D-ring as a bracelet (just the velcro thingy, without the long cable of course). I attach the camera to it.
If need to assist buddy, I either let go the housing handle amd since the rig is balanced it is not so cumbersome. Or, quickly detach from leash and reattach to harness on a single D-ring. If real emergency, will jetison the whole thing.
The leash/bracelet is also handy when transferring torch from harness to hand, or keeping double-ender while deploying SMB etc.