Readme: add more info about the initial setup and required programs

readme.md

@@ -16,8 +16,21 @@ tree ~/.local/share/histd
 ```
 
 ## Usage
+Make sure the `EDITOR` environment variable is set
+to the name of your favorite text editor.
+
+If it's not, edit the `~/.bashrc` file (or `~/.zshrc`)
+```bash
+export EDITOR=nano
+```
+
+Then mark this script as executable:
 ```bash
 chmod +x histd.sh
+```
+
+Now you can create your first note:
+```bash
 ./histd.sh
 ```
 
@@ -26,9 +39,21 @@ To create an archive of all notes, run the following command:
 ```bash
 ./histd.sh backup
 ```
+Required programs: `tar`, `xz`.
 
 ## Merge all notes
 This command concatenates all files and prefixes each with the filename.
 ```bash
 ./histd.sh merge
 ```
+
+## List all notes
+```bash
+./histd.sh list
+# /home/user/.local/share/histd
+# └── 2022
+#     └── 08
+#         ├── 18.md
+#         └── 19.md
+```
+Required programs: `tree`