I’ve started sketching out a few new garments with the help of Fashion Templates’ free technical templates. The female torso template is proportioned like an Olympic swimmer but it’s fine for sketching out ideas. They do paid ones too which I’m sure are better. Have a look at their rendering tips too if you’re thinking about brushing up your fashion illustration.
I’ve been for graph paper PDFs for planning fairisle in real size. There are lots out there, but the best one for knitting was the graph paper generator on Knitting on the Net – all you need to do is type in your required gauge, et voila! Others I looked at couldn’t produce the rectangular grid needed to accurately represent knitted stitches. Though, this variable triangle generator (scroll down) could work for the chevron shape of stocking stitch with a bit of tweaking.