````{tab} Linux
[type this into your terminal]

```
nano config/config.yml
```

I’m using `nano` here mostly because it’s simpler than any other editor on Linux.

If you see something like:
```bash
 $ nano config/config.yml
zsh: command not found: nano
```

You need to install `nano`, which you would do with:

[type this into your terminal]

```
sudo apt install nano
```

You can use any other text editor you wish, provided it saves files as PLAIN TEXT.  `vi`, `emacs`, etc.
````
````{tab} OS X
[type this into your terminal]

```
nano config/config.yml
```

I’m using `nano` here simply because it’s built into OSX.  You can use any other text editor you wish, provided it saves files as PLAIN TEXT.  BBedit, TextMate, VSCode, etc.

A common mistake is using TextEdit.app, which saves files as RTF by default.
````
````{tab} Windows
[type this into your terminal]

```
notepad .\config\config.yml
```
I’m using `notepad` here simply because it’s built into Windows.  You can use any other text editor you wish, provided it saves files as PLAIN TEXT.
````

From here on in, when this walkthrough says "open the config file", I mean this `nano` or `notepad` command.  **Don't copy the template again**.