How do blind individuals handle cash?

I remember one of my co-workers mention something about how blind individuals were wanting different denominations to be different sizes so they can tell them apart. I’ve read that right now, many of them simply fold the bills in different ways or store them in different places, but I’d think they’d still have to trust whomever gave them the money to be correct.

Sooo… how do they handle cash? Use credit/debit cards only, and avoid cash-only places? Maybe use an ATM to ensure they get 20s?

And what could be done to make it easier for them, so that they would not have to trust the teller/cashier/etc that the change they are are given is correct? I’d think that a few things would have to be changed to accommodate the different sizes.