Update README.md

Basic description and sample code

README.md

@@ -1,3 +1,100 @@
-# coordinator_ios
+# GoodCoordinator
+### 🧭 Programmatic navigation made simple, 100% SwiftUI
 
-A description of this package.
+In just 3 lines of code
+```swift
+@Push(makeHome) var home
+func makeHome(model: HomeModel) -> HomeView { HomeView(model: model) }
+
+route(to: \.home, HomeModel(username: username, password: password))
+```
+
+## Usage
+
+1. <details><summary>Implement a SwiftUI App</summary>
+
+   ```swift
+   @main struct NavigationApp: App {
+       private let coordinator = AppCoordinator(())
+
+       var body: some Scene {
+           WindowGroup {
+               coordinator.makeView()
+           }
+       }
+   }
+   ```
+
+   This is a standard implementation for a 100% SwiftUI app.
+   </details>
+
+2. <details><summary>Implement your first coordinator</summary> 
+
+   ```swift
+   import GoodCoordinator
+
+   final class AppCoordinator: NavigationCoordinator {
+       typealias Input = Void
+       typealias Output = Void
+       var state: NavigationStack = .init(debugTitle: "AppCoordinator")
+
+       @Root(makeRoot) var root
+
+       func makeRoot() -> InitialView {
+           InitialView() /// SwiftUI View!
+       }
+   }
+   ```
+
+   Don't worry about code you don't understand yet. Feel free to name the `makeRoot` function in any way you prefer. The function returns the view of your choice. However, to get this code to compile, you need to do one more thing:
+   </details>
+
+3. <details><summary>Modify your SwiftUI View a bit</summary>
+
+   ```swift
+   import GoodCoordinator
+
+   struct InitialView: View, Screen { /// Extend from Screen as well
+       ...
+   ```
+   </details>
+
+4. <details><summary>Add a navigation step</summary>
+
+   ```swift
+   @Push(makeNewScreen) var openNewScreen
+
+   func makeNewScreen() -> NewScreen {
+       NewScreen(viewModel: NewScreenViewModel())
+   }
+   ```
+
+   Add a step into your coordinator and specify, how the view will get constructed.
+   </details>
+
+5. <details><summary>Navigate!</summary>
+
+   ```swift
+   @EnvironmentObject var router: Router<AppCoordinator>
+
+   // SwiftUI view code
+   Button(action: {
+       router.coordinator.route(to: \.openNewScreen)
+   }, label: {
+       Text("Go to new screen")
+   })
+   // More SwiftUI view code
+   ```
+
+   Launch the navigation step from your view.
+   </details>
+
+## Installation
+You can use Swift Package Manager (SPM) to import this package. Use the following URL:
+
+```
+https://github.com/GoodRequest/GoodCoordinator-iOS.git
+```
+
+## Advanced examples
+TBD