Update the documentation for refreshing the Read the Docs web (#499)

docs/source/How_to/UpdateDocumentation.md

@@ -4,16 +4,24 @@ All documentation is found in the `/docs` directory.
 
 1. If you need to create a new entry, add the new document in markdown (`.md` extension) to the corresponding folder. Otherwise, just edit the corresponding file.
 
-
 > Make sure the document has one single `# header`, otherwise they will be considered different documents.
 
-
 2. If a new folder is added, add it to the `toctree` inside `docs/source/index.rst` (as the `peripherals` folder is)
 3. Commit and push
-4. Once the branch is merged into the main branch of X-HEEP, anyone can open a terminal in the docs folder and run
+
+## Refresh the web documentation
+
+After each change to the documentation, once the branch is merged into the main branch of X-HEEP, anyone must do the following:
+
+1. Open a terminal in the `docs` folder and make sure the conda environment is activated.
+2. If it is your first time updating the web docs, run:
+```bash
+pip install -r requirements.txt
+```
+3. Run
 ```bash
 make clean html
 ```
-5. Wait a few minutes and enjoy your brand new documentation in Read the Docs.
+4. Wait a few minutes and enjoy your brand new documentation in [Read the Docs](https://x-heep.readthedocs.io/en/latest/).
 
-Thank you for helping keep X-HEEP accurately and extensively documented!
+Thank you for helping keep X-HEEP accurately and extensively documented!