Obviously the packing strategy changes with each trip, but the following might be a generic 60% dirt road, 40% singletrack 3 day trip under typical Rocky Mountain summer conditions.
Seatpack: tubes and food for the next day(s) against the seatpost, tarp next, sleeping bag last (in trash compactor bag).
Frame bag: tools and pump in the bottom, food for the day, maps and clothing likely to be used through the day (arm and knee warmers, rain gear), and camera on top.
Pack: water bladder, thermarest, insulating clothing, stove, pot, odds and ends.
I'll often have a light and GPS on the bars, and perhaps an extra bottle in a cage under the downtube.
All this easily fits if you don't bring tons of extra stuff.