It's so simple, a cave man could do it.
Gold and silver are the time honored platforms of standard trade. Crypto currencies are possible supplements to this type of barter standard, but when you denominate the value of your labor in grams, ounces, or Skittlepucks of silver, gold, iron, water - or whatever, you are using a barter standard. No one else may know what a skittlepuck is, but so long as you can define it, you can mutually verify that the designated amount exists and has been exchanged.
The problem is when you have governments backing central banks. Normally, no one would buy a Federal reserve bond. All of the bank defaults and other bailouts issued by the government over the past - since we have been alive - are the Federal reserve's policies coming home to roost in proxy banks and businesses issued loans they should never have been given. Without "the full faith and credit" that you and I will hop-to in order to pay taxes, the Federal reserve imploded back before 1929 and defaulted as a relevant financial institution.
If the banking sector had to be held accountable to its own debts and assets on its balance sheets, then most of the currency problem goes away.
Case in point, most of the silver you find for sale from mints are all private mints. Some have certificates, others are the metal bar/round, but they all have a better track record than the Federal Reserve.
You can see what happened when Mt. Gox tried to run itself like a central bank. It exploded spectacularly, as it should have - and consumers learned a valuable lesson about the difference between an exchange and a magic bank of currency.