You should always check the release notes/changelog in case there are config deprecations, special update steps, etc.
Besides that, doing the following is generally enough:
# Download the new release
su pleroma -s $SHELL -lc "./bin/pleroma_ctl update"
# Migrate the database, you are advised to stop the instance before doing that
su pleroma -s $SHELL -lc "./bin/pleroma_ctl migrate"
/opt/pleroma
)git pull
. This pulls the latest changes from upstream.mix deps.get
1. This pulls in any new dependencies.mix ecto.migrate
1 2. This task performs database migrations, if there were any.