diff --git a/Writing-Test-Plan-Items.md b/Writing-Test-Plan-Items.md
index 18621c4..b28b304 100644
--- a/Writing-Test-Plan-Items.md
+++ b/Writing-Test-Plan-Items.md
@@ -235,4 +235,16 @@ Roles: Developer, Engineering Manager
 
 <!-- Please write your test here. -->
 
-```
\ No newline at end of file
+```
+
+
+## Howto: Testing Proposed and/or Latest API
+
+
+0. Make sure to have `npx`, `yeoman`, and `generator-code` installed
+1. Call `yo code` and create a new TypeScript extension (accept all defaults). You now have the default "Hello World" extension
+2. Open the extension's package.json-file and remove the `@types/vscode` dev-dependency
+3. Delete the `node_modules/@types/vscode`-folder
+4. **Latest API**: Run `cd src && npx vscode-dts main` to fetch latest stable API
+4. **Proposed API**: Run `cd src && npx vscode-dts dev` to fetch `vscode.proposed.d.ts`. Also add `enableProposedApi: true` to the `package.json`-file
+5. Press `F5` to run your extension