Update README.md

Author: Youssef1313

README.md

@@ -5,3 +5,19 @@
 
 > [!IMPORTANT]
 > This is **not** an official package produced by MSTest team at Microsoft.
+
+For examples, see [SampleUseTests](https://github.com/Youssef1313/Combinatorial.MSTest/blob/main/tests/Combinatorial.MSTest.Tests/SampleUseTests.cs).
+
+In short, the attribute `CombinatorialData` must be added along with `TestMethod`. The values used for each parameter is determined by the following rules:
+
+1. If the parameter has an attribute that implements `ICombinatorialValuesProvider`, the attribute's `GetValues` method is called to determine the possible values for the given parameter.
+    - The following attributes are already shipped and implementing `ICombinatorialValuesProvider`:
+        - `CombinatorialValuesAttribute`
+        - `CombinatorialRangeAttribute`
+        - `CombinatorialRandomDataAttribute`  
+2. Otherwise, the possible values are determined depending on the parameter type:
+    - `bool`: `true` and `false`
+    - `int`: `0` and `1`
+    - `enum`: The values as returned by `Enum.GetNames`
+    - `Nullable<T>`: The possible values of `T` plus the `null` value.
+    - Otherwise, an exception is thrown.