Update CONTRIBUTING.md to better guide new contributors

CONTRIBUTING.md

@@ -100,7 +100,7 @@ For more details on our testing setup and how to run tests, please refer to the
 
 ### ⌨️ Pull requests
 
-We welcome pull requests for editorial suggestions and resolving open issues.
+We welcome pull requests for editorial suggestions and resolving open issues. 
 
 If your pull request addresses a specific issue, please reference this issue in your pull request description using a [supported descriptor](https://docs.github.com/en/issues/tracking-your-work-with-issues/linking-a-pull-request-to-an-issue#linking-a-pull-request-to-an-issue-using-a-keyword). This helps automatically link and close the issue when the pull request is merged.
 
@@ -109,6 +109,10 @@ We strongly encourage linking every pull request to an existing issue. If no cor
 - If the issue is several years old, verify its relevance by asking in the comments.
 - Ensure the discussion within the issue has led to a clear, actionable decision.
 
+Before submitting a PR, please make sure:
+- The related Issue has already completed the [triage process](https://github.com/json-schema-org/.github/blob/main/TRIAGE.md) and has the label `Status Accepted` or `Status Available`.
+- You are assigned to work on this issue by a Maintainer or the Triage Team. Submitting a PR without getting assigned to the Issue may lead to the PR to get closed.
+
 Generally, pull requests should be made to the `main` branch.
 
 Most PRs, will be left open for a minimum of 14 days.  Minor fixes may be merged more quickly once approved by a project member.