I will mark up the pattern pages, more so with printed pdf's rather than my books...but more so to highlight the numbers for the size I'm knitting. (I'd characterize myself as a sweater knitter)
Beyond highlighting the numbers on my pattern page, I write the pattern up, piece by piece, in a notebook. Here is an example of my notes. I essentially "knit" the entire sweater before ever casting on. A "virtual knit" if you will. There isn't a sweater that I don't work out this virtual knit beforehand. Yes, it takes time, but it helps me get all the details of the sweater pieces clearly in mind and sorted out. I rarely need to frog or tink. So after my note pages are written up (using my own knitterly language and shorthand, as you can see)...my knitting zooms along...because I have really already knit the sweater in my mind and on paper. (I've blurbed out the name of the cardigan...and all 6 pieces of the cardigan are not shown. No copyright infringement.)
