I had the same problem but my instructor told me: a book devoid of scribbles is a book that hasn’t been engaged with deeply. If you have to, buy two copies of a

I had the same problem but my instructor told me: a book devoid of scribbles is a book that hasn’t been engaged with deeply. If you have to, buy two copies of a book — one for display and another to scribble in, knowing that you’ll truly own the scribbled copy because you won’t be able to sell it. Post-its work. For me I use a mechanical pencil.