Winter Graduation help

India ♊️🙌🏼🙌🏼♊️ • I'm a 27 year old mother, and wife. I'm a mother of a beautiful daughter and son. Type 1 diabetic 17 years

I will be graduating in December. The problem is, I have no idea what to wear under my gown. Right now it is 58 degrees, more than likely it is going to be cold. Any ideas, suggestions, pictures are all appreciated. Anyone else having/had a winter graduation? If so what did you wear/wearing?