Rehersal Dinner Question???

What is the norm on when to send out the Rehersal Dinner invites? Also, does anyone have a cute little saying or invitation that they used?

Any help will be greatly appreciated!!

My RD is 2 days before my wedding and I need to let the restaurant know how many people are coming 4 days before so I decided to mail them out at the end of August. Here are mine. I made them myself.