This is a simple drawing I made that I think would be great as a greeting card. I'd suggest you to print it, then add an asterisk on the right of BB8's words and write whatever you want to say on the bottom of the card (i.e " *Contratulations!"), so that your greetings would be a translation of BB8's sound.
Feel free to use it anyway you like!
Download all the files you need here: LINK