There is no step 2. You will never need to touch this again unless you change the architecture of the bot, and even then, you can probably get away with just changing the crontab.
Usage instructions
Set up the bot account as usual. Stop following the original instructions when you get to the part that runs on your own machine.
Maintainer instructions (for @Lynnesbian)
Usage instructions
docker run -ti --name my_ebooks_bot -e ebooks_site=https://botsin.space -v "$HOME/my_ebooks_bot_data_folder:/ebooks/data" --restart unless-stopped lynnesbian/mstdn-ebooks
-e
option can be skipped if your bot is on botsin.space.-v
option can be skipped to leave the data volume unnamed.Upgrade instructions
docker pull lynnesbian/mstdn-ebooks
docker stop my_ebooks_bot
docker rename my_ebooks_bot my_ebooks_bot_temp
docker run -d --name my_ebooks_bot -e ebooks_site=https://botsin.space --volumes-from my_ebooks_bot_temp --restart unless-stopped lynnesbian/mstdn-ebooks
docker rm my_ebooks_bot_temp