I recommend HW wallet like https://trezor.io Trezor is well thought off, very secure way of storing digital currency. I have been using SW wallet but switched to Trezor recently and finally I feel my coins are safe..

Just make sure to chose a good pin and passphrase (I recommend setting up both). Ideally somehow compute or derive this pin/passphrase so that you never forget it. I mean generating a random pin is a very bad idea as you will almost surely forget it over time and you will lose the wallet.

What is a ledger cold wallet?