HOW TO ADJUST YOUR MR. HYDE'S MASK:

Peter has a huge head.
It's 23.5 inches in circumference. He wears an XL hat. 
So we size the elastic cords on our masks to fit Peter.

because

If your head is smaller than Pete's,
adjusting your Mr. Hyde's Mask is a cinch.

and

If you are unfortunate enough
to have a head bigger than Pete's,
then we will gladly send you a new cord.

Here's how to adjust the elastic cord on your mask:   

 You will need a pair of sheers and a lighter.

 A.  Put the mask on and pull one of the knots at the temple through the eyelet until you have a good fit. 

B. Snip off the old knot.

 C. Make a new knot further in.

 D. Snip off the excess cording.

 E. Lightly touch the lighter flame to the end of the knot to seal it.

You're done!