I'm starting this thread for anything really easy anyone has done that they want to share 
I just 'made' this (easy copy of a posh notebook I loved from Smythsons new range) - took 10 minutes. Used a navy moleskin notebook and a white Sharpie.
Now it's not perfect 
but it didn't cost me £50 plus quid either
The first one is obviously the Smythson one.