Hello Dr. Berry,

first of all thank you for your work! If you want to learn about self-custody i recommend to watch Bitcoin University channel on youtube but also check out seedsigner. It is a DIY self-custody, airgapped device (really easy to make) and is perhaps a better solution for long-term storage of BTC. For other uses a coldcard or jade wallet are perhaps the better options. Depending on how you will self-custody it there are different things to learn.

I personally do self-custody and also use seedsigner, so if there are any questions I can help answer you please ask away.

But the most important bit - never ever tell anyone your seed words.

Kind regards!