housekeeping: add instructions how to use.

README.md

@@ -2,3 +2,68 @@
 
 This project is a .NET 5 source generator which produces `IObservable<T>` for events contained within a object including all base classes.
 
+# Installation
+
+## NuGet Packages
+
+Install the following packages to start using Observable Events.
+
+| Name                          | Platform          | NuGet                            |
+| ----------------------------- | ----------------- | -------------------------------- |
+| [ReactiveMarbles.ObservableEvents.SourceGenerator][Core]       | Core - Libary     | [![CoreBadge]][Core]             |
+
+
+[Core]: https://www.nuget.org/packages/ReactiveMarbles.ObservableEvents.SourceGenerator/
+[CoreBadge]: https://img.shields.io/nuget/v/ReactiveMarbles.ObservableEvents.SourceGenerator.svg
+
+## What does it do?
+
+ObservableEvents generator will convert events within an assembly and create observable wrappers for them. 
+
+It is based on pharmacist [Pharmacist](https://github.com/reactiveui/Pharmacist) and uses .NET Source Generator technology.
+
+## Installation
+Include the following in your .csproj file
+
+```xml
+<PackageReference Include="ReactiveMarbles.ObservableEvents.SourceGenerator" Version="1.0.2" PrivateAssets="all" />
+```
+
+The `PrivateAssets` will prevent the ObservableEvents source generator from being inherited by other projects.
+
+## How to use
+
+### Instance Based
+It injects a class for instance based events into your source code which will expose a extension method called `Events()`.
+
+You need to include the namespace `ReactiveMarbles.ObservableEvents` to access to the extension method.
+
+You can then use this to get `IObservable<T>` instances from your events.
+
+```cs
+using ReactiveMarbles.ObservableEvents;
+
+public void MyClass : INotifyPropertyChanged
+{
+  // Assumes this belong in a class with a event called PropertyChanged.
+  public void RunEvents()
+  {
+      this.Events().PropertyChanged.Subscribe(x => Console.WriteLine($"The {x} property has changed"));
+  }
+
+  public event PropertyChangedEventHandler PropertyChanged;
+}
+```
+
+### Static Events
+
+You must use include a attribute `GenerateStaticEventObservables` on the assembly level for a particular class. This will generate a class `RxEvents` in the same namespace as the specified class.
+
+```cs
+[assembly: GenerateStaticEventObservablesAttribute(typeof(StaticTest))]
+
+    public static class StaticTest
+    {
+        public static event EventHandler? TestChanged;
+    }
+```