Building Windows desktop apps involves several steps. Here is a general outline of the process:

1. Define the app: Start by clearly defining the purpose, functionality, and target audience of the app. Consider what problem it solves or what value it provides to users.

2. Design the user interface: Create wireframes or mockups of the app’s user interface (UI). Think about the layout, navigation, and visual design elements. Use tools like Adobe XD or Sketch to create high-fidelity designs.

3. Choose a development framework: Select a framework or technology stack based on your requirements and familiarity. Some popular options for building desktop apps on Windows include:

– Microsoft WinForms: a framework for building Windows desktop apps using .NET.
– Windows Presentation Foundation (WPF): a framework for building modern UIs using XAML.
– Universal Windows Platform (UWP): a framework for building apps that can run on multiple Windows devices.

4. Develop the app: Start implementing the app according to the design and requirements. Use the chosen framework and programming language (C#, VB.NET, etc.) to write the code. Follow best practices for coding and use version control systems like Git for collaboration.

5. Test the app: Conduct thorough testing to identify and fix any bugs or issues. Use testing frameworks and tools like NUnit or Microsoft Test Framework for unit testing and tools like Microsoft App Certification Kit for app validation.

6. Package and distribute the app: Once the app is stable and tested, package it for deployment. Windows offers various deployment options like Microsoft Store, ClickOnce, or traditional installer packages.

7. Publish and maintain the app: If you want to distribute the app through the Microsoft Store, create an account and submit it for certification. Once approved, it will be available for users to download. Continuously monitor and update the app to fix bugs, add features, and ensure compatibility with new Windows versions.

Remember to follow the Windows UI design guidelines and best practices to create a consistent and user-friendly app. Additionally, documenting the app’s architecture and code will help maintain and enhance it in the future.