Update README.md

README.md

@@ -4,6 +4,31 @@
 
 MYNT® EYE SDK 2.0 is a cross-platform library for MYNT® EYE cameras.
 
+## Usage
+
+```bash
+$ make
+Usage:
+  make help            show help message
+  make apidoc          make api doc
+  make opendoc         open api doc (html)
+  make init            init project
+  make build           build project
+  make test            build test and run
+  make install         install project
+  make samples         build samples
+  make ros             build ros wrapper
+  make clean|cleanall  clean generated or useless things
+```
+
+Init project, build samples and run someone.
+
+```bash
+make init
+make samples
+ ./samples/_output/bin/device/camera_d
+```
+
 ## License
 
 This project is licensed under the Apache License, Version 2.0. Copyright 2018 Slightech Co., Ltd.