Haven't got a clue what to even think about wearing so decided its best to ask the experts. Its a 'big' birthday celebration probably in a marquee but not a posh restaurant / club What would you wear ????
Definitely heels - as high as you can walk in. Nails and hair done. Full make up. If it's an evening do, probably a long dress, if day time then a good cocktail dress or trousers with silk tunic/blouse.
But someone from S&B will come along soon and tell you exactly what to wear.
Oh crikey .... Its a garden with a marquee .. There will be a dance floor however to get to the party it is down a slope....can do the nails and hair bit ...bloody hell tarts and vicars would have been easier