docs: update readme file

README.md

@@ -1,2 +1,50 @@
 # @iam1337/create-unitypackage
-WORK IN PROGRESS
+
+[**semantic-release**](https://github.com/semantic-release/semantic-release) plugin to create a [unitypackage](https://docs.unity3d.com/Manual/AssetPackages.html).
+
+[![Build Status](https://github.com/semantic-release/npm/workflows/Test/badge.svg)](https://github.com/semantic-release/npm/actions?query=workflow%3ATest+branch%3Amaster)
+[![npm latest version](https://img.shields.io/npm/v/@iam1337/create-unitypackage/latest.svg)](https://www.npmjs.com/package/@iam1337/create-unitypackage)
+
+| Step               | Description |
+|--------------------|-------------|
+| `verifyConditions` | Verify the `packageRoot`, `projectRoot` and `output` options configuration. |
+| `prepare`          | Сreation unitypackage file. |
+
+## Install
+
+```bash
+$ npm i @iam1337/create-unitypackage
+```
+
+## Usage
+
+The plugin can be configured in the [**semantic-release** configuration file](https://github.com/semantic-release/semantic-release/blob/master/docs/usage/configuration.md#configuration):
+
+```json
+{
+  "plugins": [
+    ["@iam1337/create-unitypackage", {
+			"packageRoot": "Assets/Package",
+			"projectRoot": "./",
+			"output": "Package.unitypackage"
+		}],
+    ["@semantic-release/github", {
+			"assets": [
+				{"path": "Package.unitypackage", "label": "Package v${nextRelease.version}"}
+			]
+		}]
+  ]
+}
+```
+
+## Configuration
+
+### Options
+
+| Options | Description | Default |
+|---------|-------------|---------|
+| `packageRoot` | Path to the directory you want to archive to unitypackage inside the Assets directory. | - |
+| `projectRoot` | Unity project directory. | `./` |
+| `output` | Output unitypackage path. Must end with .unitypackage. | - |
+
+**Note**: The `packageRoot` directory must have own .meta file.