Make git init example more clear (make directory first)

lectures/git/slides.qmd

@@ -28,7 +28,9 @@ There are many version control systems out there (e.g. Subversion, CVS, Mercuria
 ![](https://git-scm.com/images/logos/downloads/Git-Logo-2Color.svg "Git logo"){height=10%}
 
 ## As easy as **1, 2, 3**
-```bash
+```{.bash code-line-numbers="3-5"}
+mkdir my_repo
+cd my_repo
 git init .  # Initialize a repository
 git add .  # Add the whole directory content (don't do that)
 git commit -m "Initial commit"  # Commit your changes
@@ -82,7 +84,7 @@ git config --global user.email "youremail@yourdomain.com"
 ## Hands-on Session {background-color=var(--dark-bg-color)}
 
 1. Configure the username and email adress in your local git client
-2. Initialize an empty Git repository
+2. Create a directory and initialize a Git repository
 3. Create a file and add it to the repo
 3. Change the file, inspect the differences, and commit the changes