No piccies but in Finland recently I had a Hope Vision 2 helmet mounted along with the extension cable so that I could have the battery in my jacket chest pocket to help deal with the cold (-16C). I zip-tied the unit-to-extension connector to the helmet so that the cable didn’t get in the way too much. The extra bit of the extension was stuffed into the pocket.
Helmet light – Wire ran straight out of the light unit, loosely velcro fastened to the rear of the helmet, battery and excess wire in the back pack. On the rare occasion I rode without a pack, it just went down my back inside the jacket and into the rear pocket (I made a little hole for the wire) where the battery was.
Bars light – Had a neoprene type battery holder that had velcro straps, so straight onto the bars with any excess wire tucked into the neoprene holder. it came with the light unit from Troutie. Also seen a small camera case used and velcro’d to the bars with all excess wire tucked inside.
I can’t show, but, battery in a bottle, light on the bars as near the middle as I can, cable is too long so wrapped and loosely knotted around the bar then around whatever other cables and hoses go the same way.
I use a triathlon style top tube feed bag to hold the battery pack (2 velcro straps round the stem, 2 round the top tube). One of the bags I got is pretty sizeable too so it holds 2 battery boxes (either for two lights, or so I have a spare).