Search for a suitable tree sapling in winter, when the sap is running low in the trees. This makes for a lighter staff that won't twist and crack as it dries. Hardwoods like persimmon, dogwood, oak and maple work well. Stay away from conifers; they're soft and very sappy.
Find a tree about 1.5 inches in diameter. This size will shrink a bit during drying and a little more when you remove the bark, bringing it down to a solid inch of sturdy wood. Saw the tree off at the base.
Prune away all the branches of the tree, sawing it down to about shoulder-height. Place the staff in a cool, dry place to season for about 6 months.
Press the curved blade of a draw knife against the surface of your seasoned staff. Tilt the knife at a 45 degree angle and push it firmly away from you. This should peel away the bark easily while shaping your staff into a smooth, even cylinder. Continue until all of the bark is gone.
Sand your staff with 60 grit sand paper, moving upward in grade until you get to 400 grit. This should remove the last of the bark and make your staff silky smooth. Dust away the sawdust with a soft cloth.
Paint the staff with clear wood sealer and let it dry overnight. Sand the staff lightly with 400 grit sandpaper and add another coat of sealer. Your staff should be slick to the touch and sealed against the elements.