WordPress.org

1. Download the plugin archive and expand it (you've likely already done this).
2. Put the 'little-wp-to-twitter' directory into your wp-content/plugins/ directory.
3. Go to the Plugins page in your WordPress Administration area and click 'Activate' for little-wp-to-twitter.
4. Go to the little-wp-to-twitter Options page (Settings > Little wp to twitter) to set your Twitter account information and preferences.

下载插件，上传到插件目录，在后台管理中激活插件，到设置页面勾选“启用”并填入twitter账号密码。