Andreas Antonopoulos is a well respected speaker in the Cryptocurrency industry and many consider him the public face of the growing Cryptocurrency community. He has published 3 books (Mastering Bitcoin, The Internet of Money V1, The Internet of Money V2) and is currently working on his fourth book (Mastering Ethereum).
Check out his most recent YouTube post where Andreas talks Hardware Wallets and levels for securing Cryptocurrency. The one addition we would make to his advice is to replace the paper that is used to write your backup recovery seed with a form of metal engraving or punched metal letters (CryptoSteel) on Steel or Titanium. This allows permanency of your recovery seed and protects from water, fire, wind, accidental damage and/or the degradation of ink and paper over time.
*Extra bonus tip – You can use many Hardware Wallets as a cold storage option through your smartphone application with an extra cable. This allows you to use Cryptocurrency from your phone while still utilizing the extra security advantages of a hardware wallet.