Don't throw out an old helmet just because the padding is worn out. FIX IT!!!
This is how I did it but also check out gustapimentel's instructable doing the same thing last year.
Step 1: Easy Peasy!
Rip uot the old foam strips.
Cut new strips of foam from something, anything. My first attempt with this insole seemed to be good but it was too thick. Second try was cutting a couple of strips of foamy/EVA foam I had lying around. Perfect!
Step 2: Big Head
I have a narrow head but its quite long from front to back. I found this XXL helment that works for me years ago. And now that I'm replacing the foam strips I got the idea to customize the shape for my narrow head!!!!
No big deal, I just filled in the gaps on either side with little bits of the insole foam that was too big to go up the middle
Step 3: Finished!
Always good to fix something instead of throwing it out and buying a new one!