Yeti
Below are video walkthroughs on how to properly download, verify, and install Ubuntu on Windows 10 and macOS for the intention of a single purpose laptop. These are produced with the purpose that even people with a basic understanding in computing will be able to successfully and securely complete this task. No such tutorials exist anywhere else on the Internet.
Below is a video walkthrough of our most secure private key management scheme - Yeti Cold/Yeti Level 3. This too will walk you through every step necessary to securely store your bitcoin, and is incredibly in depth.
However, using these videos require that you trust all of the infrastructure that hosts and serves the videos to you. Therefore, I have also written a PDF that contains the same instructions of the Level 3 Yeti protocol described in the video above and on YetiCold.com. Below is this PDF, as well as my detached signature of the file. Please see 'Verification' for information on distrusting the infrastructure and verifying GPG signatures.