What can I wear to an outdoor party on Saturday???

[Bettydownthehall]

I am size 12/14 but big chest so if it's not fitted I look huuuuuge.

I have no idea what to wear. Maybe skirts and thick tights and ankle boots?

I don't know!?! Any inspiration??

What sort of party is it? I'd be tempted to wear jeans an a warm jumper!