Update README.md

Author: yimajo

README.md

@@ -10,3 +10,56 @@ The supported package managers are as follows:
 - Swift Package Manager
 - Carthage
 - CocoaPods (only supports the old format that does not use [.xcfilelist](https://blog.cocoapods.org/CocoaPods-1.7.0-beta/))
+
+# Installing
+
+## Swift Package Manager
+
+### Use as CLI
+
+```bash
+git clone https://github.com/CuriositySoftware/XcodeTargetGraphGen.git
+cd XcodeTargetGraphGen
+swift run xcgraphgen [project-file-path]
+```
+
+# Usage
+
+Simply run:
+
+```bash
+xcgraphgen [project-file-path] [OPTIONS...] 
+```
+
+```
+$ xcgraphgen -h
+OVERVIEW: Output Xcode Target Dependency Graph.
+
+USAGE: xcgraphgen [<options>] <project-file-path>
+
+ARGUMENTS:
+  <project-file-path>     .xcodeproj file path.
+
+OPTIONS:
+  --output-file-path <output-file-path>
+                          Output file path. (default: ./dependencies.md)
+  --mermaid-theme <mermaid-theme>
+                          Select Mermaid theme type (eg: neutral, forest, dark, base). (default: dark)
+  --mermaid-syntax-type <mermaid-syntax-type>
+                          Select Mermaid syntax type. (default: flowchart)
+  --mermaid-chart-direction <mermaid-chart-direction>
+                          Select Mermaid graph/flowchart direction. (default: TD)
+  --enable-swift-package-output/--disable-swift-package-output
+                          Targeting Swift Package Product for output. (default: --disable-swift-package-output)
+  --enable-apple-sdk-output/--disable-apple-sdk-output
+                          Targeting Apple SDKs for output. (default: --disable-apple-sdk-output)
+  --enable-carthage-output/--disable-carthage-output
+                          Targeting Carthage for output. (default: --enable-carthage-output)
+  --enable-cocoa-pods-output/--disable-cocoa-pods-output
+                          Targeting CocoaPods SDKs for output (only old format without .xcfilelist). (default: --enable-cocoa-pods-output)
+  --enable-vendor-output/--disable-vendor-output
+                          Targeting vendor project for output. (default: --disable-vendor-output)
+  --dry-run               Output to console without file output
+  --version               Show the version.
+  -h, --help              Show help information.
+```