All explained here:
https://darth-coin.github.io/beginner/getting-started-stack-sats-en.html
And
https://darth-coin.github.io/beginner/be-your-own-bank-en.html
And
https://darth-coin.github.io/wallets/tails-hodl-cold-wallet-en.html
And
https://darth-coin.github.io/wallets/deposit-only-btc-wallets-en.html

DarthCoin

At how much stack do you think a stacker should start using cold storage?

bitcoin_beginners

Questions about your cold wallets rotation

Thank you Darth. 
At how much stack do you think a stacker should start using cold storage?