The offline mode of securing bitcoins is called cold storage. Cold storage wallets are not connected to the Internet and are thus less susceptible to hacking. Since accessing a cold storage wallet can be inconvenient, its best to split the bitcoins you own. Keep a small amount of bitcoins in an online digital wallet for daily trading needs and keep the rest in cold storage. Cold storage takes the private keys in an offline mode, thus decreasing the chances of theft. The practice of using cold storage is not only popular with individuals but even with cryptocurrency exchanges that deal with huge sums and are often under constant threat by hackers. The popular cold storage methods are paper wallet, sound wallets, storage devices (like a USB drive), and hardware wallets.
Keep your software up to date. A wallet running on non-updated bitcoin software can be a soft target for hackers. The latest version of wallet software will have a better security system in place thereby increasing the safety of your bitcoins. If your software is updated with the latest security fixes and protocol, you may evade a big crisis because of the enhanced security of the wallet. Consistently update your mobile device or computer operating systems and software to make your bitcoins safer.