What we did was to position the ear pieces correctly in the helmet, then pulled the side cheeks out of our helmets (arais), trimmed the foam on them, and put the ear pieces under the lining of them. This stops them from moving about every time you put the helmet on.
Before we did this we found the ear pieces would presss on the tops of our ears and make them hurt after a days riding.
I also tie-wrapped the cable end to one of the cheeks (pushed tie-wrap therough behind foam and plastic backing). We found the cabling kept getting pulled out otherwise.
One final tip - make sure you put the mic boom the right way around as it says in the instructions, and have it so that when you purse your lips you can just touch it. If it is further away your partner won't be able to hear you at speed for all the wind noise.
Hope that helps
