When I read, I have a pen and a slip of paper nearby - not a pad. The paper cannot be blank. A scrap piece of mail - something printed already or, at fervent last resort, a clean napkin. I find that I can only jot notes on non-white surfaces or my hand. Blank paper and large notepads are too daunting, seemingly imploring a stroke of genius.
Likewise, when I write, I always have reading material within reach - not a dictionary or another composition tool, but a magazine or an essay, but never something that I, myself, have written. I don’t even have to read it (though sometimes I do); it just needs to be there for comfort, like a stuffed animal given to a toddler.