How can you shrink a mesh baseball hat?

Answer 1

put it in the microwave also try a packet of crisps it goes all shrivelled and tiny

Turn your oven to 300 degrees and put hat in. notice that the hat must have soaked in water for ten minutes before it enters the oven. Leave the hat in for 30 minutes. Take it out and wet in again. Just a sprinkle the second time. Put it on for half an hour then bam there you go. And dont forget to be naked while you are doing it.

If the hat has any plastic it will melt in the oven, even when wet.

Answer 2

What is it made of? If it is a wool felt, no you will ruin it. Most hats you can't shrink, but here is an idea put in a false head band inside the hat so it will fit your head.