Picking up stitches from purl

Hello everyone!
I am making these: http://www.purlbee.com/mary-jane-slippers/
and am having an issue picking up the stitches after binding off the sole. I get picking up these stitches on a horizontal edge, however on the vertical edge, I’m clueless. I can find tutorials on doing it if the stitches appeared as knit stitches, but these are purl-looking stitches. Does anyone have any advice, or better yet, a visual for me? I’d very much appreciate any advice!
Thank you!:yay:

If you’re picking up in garter stitch, most patterns have you pick up a stitch in the ridge, the purl bump (search for a tutorial for the Mason-Dixon log cabin blanket, I think there’s one on their website), but I think it’s easier to find the sts in the ‘valleys’. Just make sure you insert the needle through two strands and for garter, you pick up in every other stitch.