diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 759ec6fb9..ac8e98def 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -14,6 +14,7 @@ We like to discuss things before implementation and want to be sure that:
 
 ## Pull Requests
 
+- [Create a new Git branch](https://help.github.com/en/github/collaborating-with-issues-and-pull-requests/creating-and-deleting-branches-within-your-repository). Don't use `master` branch for PR.
 - All Git commits are required to be [signed](https://docs.github.com/en/authentication/managing-commit-signature-verification/about-commit-signature-verification) to be marked as "Verified": signed with a GPG, SSH, or S/MIME that is successfully verified by GitHub. For changing a single commit after creating the PR, use `git commit -S --amend` and force push the branch.
 - All tests must be green before merge.
 - Hurl git history is linear, so we ask to rebase your PR before final merge.