What do I wear to a graduation?

[fhdl34]

My husband is graduating in October and I am wondering what I should wear? I will have to buy something as I have nothing appropriate at all.
I am losing weight so do not intend to buy anything till a week or so before but we have very little money so I am thinking I will sell it on afterwards.
I have just gone into a size 24-22 and I am 5ft 2in, I'll possibly have lost another stone by then so would think I'll be comfortably a 22.
I am not a dressy person, when I last went to a wedding I wore a maxi dress and little shrug set I got from Ann Harvey as I was breastfeeding and I felt really comfortable in it.
I will have very little hair too as I am shaving my head next month for charity so I would like something that makes me look good.
Any ideas? I usually shop at Yours and live in jeans or cropped trousers and vests or long tops. I am thinking a dress or skirt and top would be nice.
Any advice is appreciated as I am hopeless with fashion

Something smart that looks good in a photograph years later. The sales are on at the moment so have a look . I would also look in Charity shops if you don't want to spend a fortune and you might not wear it again that often. I have picked up some real bargains in the past.

Thanks, I never consider charity shops because of my size but they must have bigger sizes as I give my stuff to charity when I'm done with it. I usually buy off eBay but if it's a bad fit I'm stuck with it