diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index cf38401..99e0812 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -5,6 +5,11 @@ Run Cypress integration tests in Chrome browser.
 - `npm run dev` to start local server.
 - `npm run test`
 
+## Adding tests
+
+- Update `cypress/test-pages/index.html` as needed or create a new test page if you need new examples.
+- Add new tests in `cypress/integration/apis_spec.js`
+
 ## Making a new release
 
 - Update version number in `src/color-thief.js` and `package.json`