If you tried to write Unit Tests before, you know it can be hard. If you are looking for a little guidance, check the Unit Testing Examples and Labs on Github created by Dan Hellem.
It covers the very basics to more in-depth materials such as dependency injection, mocking, and TDD. Here is the full list of covered topics:
- MSTest Unit Testing Basics
- Mocking Frameworks
- Dependency Injection
- Data Driven Tests
- SSDT (Testing Stored Procedures)
- Web Api Rest Services