Obvious philosophy is to minimize weight and bulk whenever possible. Bivy bag shelter, down bag, 3/4 sleeping pad can all reduce big bulk if camping overnight compared to full size options. Compression bags help keep things tight and compact. A tank bag, fanny pack,or backpack can keep frequently needed items close at hand so that you are not digging and repacking throughout day for camera, snack, beverage, sunsceeen, map, whatever.
I would test pack and load in advance, then re-evaluate and maybe cull what you take because Murphy's Law corollary#2 states that the mess will usually expand to fill the available space. You have back-packing gear or experience?
Lots of more experienced riders here than me, somebody help nunya with itemized suggestions.