Hello 白い熊,

I can also recommend the new Guix tutorial videos.

They are currently located here:

https://archive.org/details/guix-videos

(When finalized, they should move to a GNU website.)

I especially recommend the "packaging" videos, where a setup from git
is shown. It is doing things step-by-step. If you are then stuck with
any problem, you might also like to ask for help on IRC.

Björn