Here we go:

Example files

Any place you see , you need to change it to fit and omit the <>. If something in two differet places like this, make sure they match when you're done as well. Specifically, the postgres user and password in the lemmy docker file and the lemmy.hjson.

Finally, in Google drive the files end in .txt so you can view them. You'll need to correct the file names when you download them if you intend to use them. You should have two docker-compose.yml, one in each of the two directories you create, and one lemmy.hjson.

From a fresh CLI Debian 11 install:

su
/sbin/usermod -aG sudo <user>
groups <user>
apt-get install sudo
cd /opt
mkdir npm
cd npm
(copy or create docker-compose.yml)
apt-get install docker-compose
docker-compose up -d
cd /opt
mkdir lemmy
cd lemmy
(copy or create docker-compose.yml and lemmy.hjson)
mkdir -p volumes/pictrs
chown -R 991:991 volumes/pictrs
docker-compose up -d
docker ps (verify containers are all running, grab ip address for lemmy container)
Configure port forwarding in npm for your lemmy container (npm should be accessible at debian_ip_address:81)
Remember to do the custom paths from the various guides. The lemmy port in this guide is 1234.

Please note I am not addressing federation or SSL or true hosting yet. I haven't got that far yet. But if you can get the damn thing running, the last mile shouldn't be too bad.