Yay for you!!!!
Honestly- when I make my commute home from work longer, I just wear what I wore at work on top and put some capri cycling tights on the bottom. Just wear whatever you are comfortable in. If you were comfy in what you wore yesterday- then wear that again. Whatever makes you FEEL comfy will be comfy. I didn't feel comfy wearing jerseys and tights at first, so most of my rides at first were just a looser dri-fit shirt and baggy shorts over cycling shorts.