doc(readme) introduce how to use the tool

README.md

@@ -1,14 +1,49 @@
 # media-get
 Get the media through the url
 
+## Quick Start
+```shell
+# download the bilibili video with the url
+media-get -u "https://www.bilibili.com/video/BV1eb4y187AG?spm_id_from=444.41.0.0"
 
+# only download the audio, use `-t audio`
+media-get -u "https://www.bilibili.com/video/BV1eb4y187AG?spm_id_from=444.41.0.0" -t audio
+```
+
+## Download / Update the tool
+One of the following way can be download
+- from the latest release page. [Click me](https://github.com/foamzou/media-get/releases)
+- brew install (soon...)
+
+## Usage
+```shell
+Usage:
+  media-get [OPTIONS]
+
+Application Options:
+  -u, --url=         Url from website. Start with http[s]://
+  -o, --out=         The output file will be place to here(dir/filename). Default: current dir
+  -t, --type=        The resource type you want to get [auto/audio/video/all] (default: auto)
+      --addMediaTag  Add media tag into file from meta information. Default: false
+  -m, --metaOnly     Output meta info only. Would not download audio
+      --metaFormat=  Support plain/json. Default: plain
+
+Help Options:
+  -h, --help         Show this help message
+```
 
 ## Build
+```shell
+# linux
 CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build main.go
 
+# windows
 CGO_ENABLED=0 GOOS=windows GOARCH=amd64 go build main.go
 
+# macos
 CGO_ENABLED=0 GOOS=darwin GOARCH=amd64 go build main.go
+```
+
 
 ## Thanks
 - Netease Encrypt Method: https://github.com/872409/music-get