This is a short guide for keeping your cryptocurrencies safe.
As a generale rule, you should follow these practices:
- Do not keep money on exchanges
- Do not use web-wallets
- Do not talk to anyone about your money
Exchanges get hacked. Make your trades and withdraw to an external wallet. In any case, protect your account with 2fa.
Web-wallets, even claiming to be open-source, can easily get compromised.
Treat crypto like cash. Don't communicate about your earnings on social media or to other persons. Do not tell people where you store it, do not tell people how you store it. Trust no one.
Encrypt your wallet seeds (for example with pgp) using a long passphrase containing symbols. Save it in several locations (virtual and physical).
However, you stay vulnerable to keyloggers or other malwares upon decryption. If you hold large amounts, you should only decrypt it on a live cd running offline.
Alternatively, you can purchase a hardware wallet, like a Ledger Nano or a Trezor. It won't communicate sensitive data with the computer. Buy it directly from the manufacturer (scams exist). Use a pin (or passphrase) in case it gets stolen. Back up the recovery words encrypted or memorize them.