OK guys! HERE's MY SOLUTION!
FIRST excuse my english, i'm french...
you'll need :
-skullcandy icon 2s
-helmet : SALOMON BRIGADE
-pieces of foam or something soft and quite thick.
step 1 :
Take off the backstrap of the helmet by pulling hard on it, should comme quite easily.
step 2 :
turn it upside down and with the 2 nails, attach the torn part to the inside of the helmet as shown on the bottom right picture,be sure to let enoughe space for the icon 2 to fit in. put the foam beetween the nail and the strap, as shown on the picture.
step 3 :
put it on you head, with the skullcandy around your neck, be sure to put the left speaker on the right side and vice-versa.
step 4 :
using the button, put the headstrap of the icon 2, inside what you just attached to the helmet.
you're welcome :)