added contributing guidelines

CONTRIBUTING.md

@@ -0,0 +1,24 @@
+# How to Contribute
+
+We'd love to accept your patches and contributions to this project.
+There are just a few small guidelines you need to follow.
+
+## Developer Certificate of Origin
+
+Contributions to this project must be accompanied by a Developer 
+Certificate of Origin statement agreement. You (or your employer) retain the copyright to your
+contribution; this simply gives us permission to use and redistribute
+your contributions as part of the project. Head over to
+[https://developercertificate.org](https://developercertificate.org)
+to see the text of the agreement. When you're signin-off your update it means that you agree with the 
+Developer Certificate of Origin statements.
+
+## Code reviews
+
+All submissions, including submissions by project members, require review.
+We use GitHub pull requests for this purpose.
+Consult [GitHub Help](https://help.github.com/articles/about-pull-requests/) for more information on using pull requests.
+
+## Community Guidelines
+
+This project follows [Contributor Covenant Code of Conduct](CODE_OF_CONDUCT.md).

README.md

@@ -51,6 +51,10 @@ backend option offers 5 thin metal layers, two thick metal layers (2 and 3 μm t
 * MOS/HBT Measurements in MDM format
 * Project Roadmap Gantt chart
 
+## Contributing
+
+Thank you for considering contributing to IHP Open Source PDK project on GitHub! To get started, please fork the repository and create a new branch for your contributions. Whether you're interested in code improvements, bug fixes, feature additions, or documentation enhancements, your input is invaluable. Please ensure your code adheres to [GitHub coding standards](https://github.com/git/git/blob/master/Documentation/CodingGuidelines) and accompanies appropriate tests. Please see the [Contributing file](CONTRIBUTING.md) for additional details. We appreciate your support and look forward to collaborating with you!
+
 # About IHP
 
 **The IHP is a non-university research establishment institutionally funded by the German federal and state governments and a member of the Leibniz Association.**