Download wordpress plugin

 - If you use wordpress plugin, upload plugin to wp-content/plugins directory. Enter wordpress admin panel and activate plugin.

 - After that enter enter Settings>Backlink page and fill areas your backlinkedu.com username, password and sitekey

 - Go to Appearance->Widgets and move Backlink widget from available widgets to sidebar 1 . Change widget title as optional

Everything is this, Your site will join exchange next update