So, you have two choices. Will it make you happier to either:
1, Use an old notebook I have laying around. It will make me happy to have a use for it, It will save money, too, and even some trees.
2. Get a brand new special notebook, one that I love to look at, touch, to smell the nice paper.
Whichever one suits you is fine...just so long as you have it ready to go by Monday morning.
If you want, you can even set aside a special pen...one that you really like and feels nice in your hand.