Backup your WordPress installation files and database.
Install and activate the plugin
Add the new plugin you have received and activate it:
Go to Plugins > Add New > Upload and click the Browse… button to select the plugin’s zip file,
usually media-instagram-x.y.z.zip (x, y and z are the plugin’s current version numbers).
After that proceed to activate the plugin.
1.- Register your application in: http://instagram.com/developer
2.- Register the client in: http://instagram.com/developer/clients/manage
Setup WordPress Media from Instagram
You only need your Instagram username and the access token.
You can get your access token, using this web app: http://www.pinceladasdaweb.com.br/instagram/access-token/
Once the plugin is installed, enabled and configured, it begins to run.
In Media -> Media Instagram menu you can see your Instagram images.
Only one step is needed:
1.- Select the images you can upload and click “Upload to Media”.
That is all in your WordPress Media already are the images available.