What a wonderful thought being a woman (female). I can think of many things that I would want to do. However, it would be impossible to experience everything in just one day. I would just have to get out and see what could be possible. Here are some thoughts.
Spend the day WITH MY WIFE
as a woman 
both publically and privately.Begin by dressing casually (hopefully unisex or as feminine as possible) in weather appropriate clothing.
Go shopping for some needed feminine clothing; using the store fitting rooms as necessary.
Use the women's public restrooms when necessary. Definitely not the men's restrooms.
Go to a mixed sex gym or exercise facility; using the available facilities, changing rooms, and showers.
Go swimming at a public beach or a mixed sex public swimming pool; wearing a tankin1 suit and using the changing rooms and showers.
Just do anything for the enjoyment of socially being a female and having a female body and genitals.
Maintain intimate sexual contact with my wife whenever and where ever possible. I know that is being a lesbian but I love her and enjoy being with her. I don't have any real desire to be intimate with a man or to have a penis stuck in me so that would not be on my list of possible one day activities. It might be a worthwhile one-time experience if I could permanently remain a female.
Be sad
thinking about the experience having to end. Be thankful to no longer have a penis and testicles. Hope to keep the female body 
and genitals forever.
