In a nutshell, everfree2 wants to send a message to Ayu on her birthday. At
Ayunite!, there was a link which was posted to sending a message to Ayu:
http://hp.kutikomi.net/aw_ayu_love/?n=page11
If you click the top link on the 2 pages, you'll see a Japanese BBS in which you can write a message to Ayu (I believe any language is allowed), with those messages being sent to Ayu via CD-R. As for the party everfree2 is referring to, I believe it might be similar to the party he held a few months ago, in which I think Isaac and Kawai attended the event. So overall, I'm guessing that he's asking for ideas for the party to celebrate Ayu's birthday to coincide with the birthday messages.