Merge pull request #17 from nifcloud/feature/more_friendly_usage

Add more usage contents in README

README.md

@@ -35,22 +35,61 @@ $ docker run -it --rm ghcr.io/nifcloud/nifcloud-cli --version
 
 ## Usage
 
+### Set credentials
+
+You can configure credentials via environment variables or `nifcloud configure` command.
+
+#### via environment variable
+
+- Linux
+
 ```
-## Set credentials and default region
 $ export NIFCLOUD_ACCESS_KEY_ID=<Your NIFCLOUD Access Key ID>
 $ export NIFCLOUD_SECRET_ACCESS_KEY=<Your NIFCLOUD Secret Access Key>
 $ export NIFCLOUD_DEFAULT_REGION=jp-east-1
+```
+
+- Windows
+
+```
+C:\> set NIFCLOUD_ACCESS_KEY_ID=<Your NIFCLOUD Access Key ID>
+C:\> set NIFCLOUD_SECRET_ACCESS_KEY=<Your NIFCLOUD Secret Access Key>
+C:\> set NIFCLOUD_DEFAULT_REGION=jp-east-1
+```
+
+#### via `nifcloud configure` command
+
+```
+$ nifcloud configure
+NIFCLOUD Access Key ID [None]: <Your NIFCLOUD Access Key ID>
+NIFCLOUD Secret Access Key [None]: <Your NIFCLOUD Secret Access Key>
+Default region name [jp-east-1]: jp-east-1
+Default output format [None]:
+```
 
-## Show available services
+config file is saved under the `.nifcloud` directory in your home directory (`$HOME` or `%UserProfile%`)
+
+### Show available services
+
+```
 $ nifcloud help
+```
+
+### Show available actions for the service
 
-## Show available actions for the service
+```
 $ nifcloud computing help
+```
+
+### Show available parameters for the action
 
-## Show available parameters for the action
+```
 $ nifcloud computing create-key-pair help
+```
+
+### Run the command actually
 
-## Run the command actually
+```
 $ nifcloud computing create-key-pair --key-name foobar123 --password foobar123 
 ```