[doc] Improve install_poetry doc

doc/install_poetry.md

@@ -18,10 +18,17 @@ sudo apt install libffi-dev # Required on ARMbian
 pip3 install poetry --user
 ```
 
-### Install dependencies and the Python environment
+### Install dependencies and the Python virtual environment
 ```bash
-git clone https://git.duniter.org/clients/python/silkaj
+# Over HTTPS
+git clone https://git.duniter.org/clients/python/silkaj.git
+
+# Over SSH
+git clone git@git.duniter.org:clients/python/silkaj.git
+
 cd silkaj
+
+# Installs the runtime and development dependencies
 poetry install
 ```
 
@@ -31,11 +38,24 @@ Within `silkaj` repository run Silkaj:
 poetry run silkaj
 ```
 
-You might need to enter Poetry shell to access development tools such as `pytest` or `black`.
+### Poetry shell
+You can access tools (`pytest`, `black`) from within the development environment with `poetry run` or by entering the shell:
+```bash
+silkaj> poetry run pytest
+silkaj> poetry run black
+```
+
+```bash
+silkaj> poetry shell
+(silkaj-58dUTebQ-py3.9) silkaj> black
+(silkaj-58dUTebQ-py3.9) silkaj> pytest
+```
 
 ### Make Silkaj accessible from everywhere
-
 Add following alias to your shell configuration:
 ```bash
-alias silkaj="cd /path/to/silkaj/silkaj && poetry run silkaj"
+alias silkaj="cd /path/to/silkaj && poetry run silkaj"
 ```
+
+### Contribute
+Follow the [contributing guide](CONTRIBUTING.md).