My first notebook DIY is with spray paint. You can take whatever colour you like, but I took a gold spray paint. I used a huge bag to lay my notebook on and then sprayed the paint over it. I did 3 layers of spray paint.
My second notebook DIY is how to wrap a notebook with wrapping paper. You can again choose whatever wrapping paper you want, but I chose a cute owl print. The first thing you do is choose the wrapping paper you want and cut it. Leave some space so you can later wrap it around the notebook. The second thing you do is cut two pieces out of the wrapping paper. These pieces will make it easier to wrap your paper around the notebook. These pieces are 2cm wide. The third thing you do is wrap the paper around the long side of your notebook. Do it on both sides. Then you can wrap the paper around the other sides (upper and lower side). Use sticky tape so the paper won't get loose. And then your notebook is wrapped (5 & 6).