feat: Cleanup readme for initial release (#6)

Author: AngelOnFira

Assets/Rivet/Editor/Images/icon-text-black.svg

@@ -1,14 +1,65 @@
-# Unity Plugin (Coming Soon)
+<p align="center">
+    <picture>
+        <source media="(prefers-color-scheme: dark)" srcset="Assets/Rivet/Editor/Images/icon-text-white.svg">
+        <img src="Assets/Rivet/Editor/Images/icon-text-black.svg">
+    </picture>
+</p>
+<h1 align="center">Rivet Unity Plugin</h1>
+<p align="center">
+    <a href="https://rivet.gg/discord"><img src="https://img.shields.io/discord/822914074136018994"></a>
+</p>
 
-Placeholder repository for the Rivet Unity plugin coming soon. [Join our Discord](https://discord.gg/aXYfyNxYVn) to get access to the Unity plugin.
+Source for the Rivet Unity plugin. [Join our
+Discord](https://discord.gg/aXYfyNxYVn) to get help. Check out our [Unity
+FishNet
+example](https://github.com/rivet-gg/examples/tree/main/unity/tanks-fishnet) to
+get started today.
 
-See also our WIP [Unity FishNet example](https://github.com/rivet-gg/example-tanks-unity-fishnet) to get started today.
+## 📦 Installation
 
-## Installation
+You can install the Rivet Unity plugin in a couple ways:
 
-_Coming soon_
+- **Import a Unity Asset**: Go to the latest release on the [releases
+  page](https://github.com/rivet-gg/plugin-unity/releases)
+- **Unity Package**: Use this Git URL in the Package Manager:
+  https://github.com/rivet-gg/plugin-unity.git?path=Assets/Rivet
+- **Manual Install**: Clone this repository and copy the `Assets/Rivet` folder
+  into your Unity project
+- **Unity Asset Store**: Coming soon!
 
-## Getting started
+## 🚀 Getting started
 
-[Getting started guide](https://rivet.gg/learn/unity)
+Head over to our [Learning Center](https://rivet.gg/learn/godot) to get started
+with Rivet and Godot.  
 
+## 🧐 Features
+
+### Link your game with Rivet
+
+One click and your game is connected! Linking your game with Rivet gives you
+one-click deployments to production, easy playtesting setup, and ways to
+configure your game's hosting and matchmaking.  
+
+### Deploy your game
+
+Without the use of any command line commands, Rivet plugin lets you deploy your
+game server in no time.
+
+### Manage your tokens
+
+Rivet lets you test your multiplayer games in multiple ways. Don't worry about
+using any complicated commands, this plugin keeps you covered.
+
+_and much more coming soon!_
+
+## 🏗️ Contributing
+
+1. Look for any issue that describes something that needs to be done - or, if
+   you're willing to add a new feature, create a new issue with an appropriate
+   description.
+    - You can follow [Rivet RFCs](https://github.com/rivet-gg/rfcs) if you want
+      to be up to date with upcoming features.
+2. Submit your pull request.
+3. Rivet team will review your changes.
+4. Don't forget to join [Rivet's Discord](https://rivet.gg/discord) to hang out
+   with the devs, or to pairprogram together!