Below is another outfit Jean Shrimpton wore to the Melbourne Cup in 1965. This outfit is more conservative than her first in that it is a suit rather than a whimsical dress and a hat is worn rather than not and that hat is fantastic:
Those in the know these days tell us that the fashion choices for Melbourne Cup Day should be somewhat relaxed as opposed to
Derby Day which is quite formal. At the Cup today, there was a mixture of 'relaxed' and 'formal'. Some ladies dressed up and others dressed down and there were many styles worn which can be related back to the eras of the 1950's and 1960's!
So, keeping in mind that the dress code for Melbourne Cup day is more relaxed that Derby Day and having seen there is a lovely mixture of semi casual and semi formal, I think I'll go for a more formal look, like the lady above.