Graduation dress

[dreamingofkrispykreme]

Hello, after some advice, I have my graduation coming up and am totally unsure what to wear! Need some links/tips advice please. I am a size 4, (can wear asos 2, sometimes a topshop 6) 5ft 3.
The only problem is huge money issues (can not wait to be employed and paid), so I will be looking on ebay for the styles/dresses suggested.

Also will need shoes? Are open toes a huge no? (I have opened toed shoes I can walk in).
I am graduating from Plymouth uni if this makes any difference.