Dispose of carefully, make sure to obscure the addresses, names, serial numbers, account numbers, monetary amounts, start date, expiry and the rest.
Despite the online security craze, the offline letter in the mailbox still has all the details.
Don’t worry it’ll soon all be replaced by a system which will be much better and much easier to use.
In the meantime, make up truly good gobbledygook passwords, cut, rip and dissolve or double-shred paper documents and relax.
A game can be made of it. Then, after that, play an “actual’ game.