You can protect your private keys with hardware storage's which can be USB or Hardware Storage Modules (Physical computing devices that safeguard and manage digital keys). Another way to protect your private keys is by using a local file system. A file system enables applications to store and retrieve files (your private keys) on storage devices. You can also protect your private keys by simply printing your QR code and private key on a piece of paper and keeping that in a secure place. This is the least ideal option.