First of all, you should look at the tutorials I've written on building boffers:
http://www.arsmagicae.com/howto.html
Secondly, wielding a dagger and a short sword is a BAD idea. Boffer combat is all about speed, so with two short weapons you'll take longer to close, meaning you will take blows EVERY time you TRY to get close enough to land a few. Two shortswords is a somewhat workable style, but you'll still be at a terrible disadvantage against long weapons.
The next comment I am going to make is in no way intended to be sexist. Women are at a disadvantage in combat. We have less muscle mass than men and are not encouraged to be as active. This means the weapons that will likely work best for you are ones that will give you reach and range. This, by the way, is why my character Nara fights with a polearm and a pistol: I compensate for bad wrists and slower reflexes but wielding a weapon with reach and having a ranged attack as a back-up. Polearm is an easier style to learn to fight than dual short. I don't have the materials to make you a polearm, so I recommend you just ask MonsterCamp nicely if you can borrow a weapon for the event.
I know you want to have a cool character and not do what everyone else does, but if you plan on doing any combat, I want you to have fun and not be frustrated that you're losing every fight. Unless you're a marital arts mater, you will loose most battles with a short sword and a dagger.
--Nara Darkstrider
Mercenary Guildmaster