I love the story of Delta Pi!
That said, last fall my colony was at 6; today we are at 16.
I know some things that help are good publicity when you aren't around (if that makes any sense) - publicity when you are there (ie, letter shirts) helps too though.
For example, at my school, every Greek organization has a "board" (a bulletin board that is locked with a glass window) to display photos, put up flyers, show letters and symbols (we put fake yellow roses in there), etc. People look at them a lot. Talk to your Greek Advisor or Director of Student Life to see if there is anything like that that could become available to you. You may want to urge Delta Zeta to do one too; or you could do a Panhellenic one maybe.
Keep submitting articles to the school newspaper about service, etc. (and pictures if you can). (Lol, just found one - the "Miss AST" thing sounds adorable! How did that go?)
Another example - you really need a website. I can help you if you like; I am our webmistress. Upload your website to the school server (most schools let organizations have a free website on the server) so that students can find it when they search. This way, if a girl is shy or doesn't know who to ask about AST, she can find out more on her own time.
We also paint the rock - spray paint our letters on a boulder near the soccer field. It is a tradition on campus, and all GLOs do it. Are there any traditions like that on your campus? Make sure to be active in them!
Make cute, unique AST letters to put in the window of every girl in your sorority!
Do chants / cheers every so often, just for fun. We do these in the yard area by the girl's dorm before a dorm storm sometimes, and people come out and clap for us. It's pretty cool, and it gets people involved. We do two chants or so before we go.
Don't just focus on recruitment!!!
I love the visible community service ideas.
You also need to have swaps (doesn't have to be a huge planned-out swap - it can be going bowling, pizza and a movie night, etc.) with as many fraternities as you can ASAP. Take lots of pictures! Many girls would be so excited to be involved in fraternity swaps. Use them in your new PR things like board, newspaper, and website. Also, guys talk - have fun with them, and they might say something to their girlfriends about how fun Greek life is and how they really should try to rush AST.
Have an all-sorority social event too (go out for ice cream or something) to get to know the ladies of AKA and DZ. You'll ahve fun, and you'll be able to work together better. Also, how big is AKA?
Don't underestimate commuters. They can be valuable members of your sorority! Many of them are also unsure of how to meet new people and get involved on campus. Tell them about all the exciting events you have planned for this semester, and invite them to hang out (informally) with y'all sometime. Make flyers and hand them out in a commuter lounge, commuter parking lot, building with a lot of night classes, or whatever. List things like "socials with fraternities", "fun sisterhood activities", and "community service" - and give a few examples of each. Don't just write "Rush AST" - it won't help much if they don't know anything about AST.
Good luck!!
I would still love to help with your website - PM me if you would like help with that or anything else!
Tau love and mine,
Marly