Just got a new dx extreme helmet mounted light, but cant figure out how to fit the strap and holding onto my helmet. Any idea's

Its 2 straps in a thong shape if that helps

Well, it seems the strap is designed like Petzl head torches – i.e. head not helmet mount. I worked out a way by unpicking the loop and the doubled over end of the other part then just used them like regular straps.

I have a central brace on my lid so I looped the back strap around that and under the mount to tighten it in one plane then used the other strap to do the lateral stability.

In short you will just have to experiment

i ended up doing nearly that in the end, by making 2 loose ends from the side and back strap and just tightened them centrally on the top of my helmet. Testing tonight to see if it works
🙂