Posting to Facebook really is as simple as just posting your ThisCrush URL as a status and Facebook will take care of the rest.
Just in case that's not easy enough, you can click the Facebook "f" logo on the left side of your Crush Page (while logged in) to post a link on your Facebook! It will pop up a status window that includes your ThisCrush URL and you can add any text you wish to include.
If you need to find your ThisCrush URL you can use this page: http://www.thiscrush.com/code.php
Simply enter your ThisCrush Username and then copy what shows up in the "Your CrushTag Address" box.