Add more remarks

docs/topics/creation.md

@@ -19,6 +19,23 @@ so ensure you trust it!
 * [tasks and migrations][tasks-migrations]
 :::
 
+## First steps
+
+Many operations in your Salt extension project require to be run inside an initialized Git repository
+and a Python virtual environment with your project installed.
+
+The following steps are therefore necessary to finish your project generation:
+
+```bash
+git init
+python -m venv venv
+source venv/bin/activate
+python -m pip install -e '.[tests,dev,docs]'
+python -m pre-commit install
+git add .
+git commit -m "Initial extension layout"  # Can fail, just add the changes and repeat
+```
+
 ## Important considerations
 TODO
 ### Organization or individual

docs/topics/extraction.md

@@ -1,2 +1,16 @@
 # Extraction of Salt core modules
 TODO - ref https://github.com/salt-extensions/extension_migration
+
+## Gotchas
+### Unit test imports
+
+Unit tests import the modules directly. After migration, these imports
+need to be adjusted, otherwise the tests will run against the modules found in Salt, but still pass (or fail once they are removed). Example:
+
+```python
+# Old import
+from salt.modules import vault
+
+# Correct
+from saltext.vault.modules import vault
+```