diff --git a/PACKAGING.md b/PACKAGING.md
index 6da1a26..4f3e079 100644
--- a/PACKAGING.md
+++ b/PACKAGING.md
@@ -11,7 +11,7 @@ for instructions.
 
 ## Creating the package
 Use Docker/Podman to avoid screwing up your main system.
-For example, to create a package for bullseye:
+For example, to create a package for bullseye (replace `podman` with `docker` in all instances below if you're using Docker):
 ```sh
 podman run -it --name pyceo-packaging -v "$PWD":"$PWD" -w "$PWD" debian:bullseye bash
 ```
@@ -22,6 +22,7 @@ Docker image (this is because the virtualenv symlinks python to the OS' version
 Here are some of the prerequisites you'll need to build the deb files
 (run this inside the container):
 ```sh
+apt update
 apt install devscripts debhelper git-buildpackage
 ```
 Make sure to also install all of the packages in the 'Build-Depends' section in debian/control.