Use an umbrella.
No amount of waterproof clothing provides 100 percent protection from a true deluge. A lightweight umbrella is a cheap and effective way to shrug off lots of moisture. Rig a hands-free system by duct-taping yours to a trekking pole or stick; lash that to the side of your pack.
Bring two half-liter bottles.
Not just for water, but for drying socks at night. You'll want the narrow, Lexan type because you're going to fill them with boiling water and roll your wrung-out socks over them. The odors unleashed might make a skunk gag, but by morning your socks will be dry.
Waterproof your pack.
Most good packs are built from waterproof fabric but have seams that leak like sieves. Solution: Make sure to buy a seam sealer to prevent zippers and other closures from leaking
Gaiters under your rain pants will keep your boots and feet dry in the heaviest of downpours.
Use nature's umbrella.
Take breaks under overhangs or thick fir trees.
Care for your gear.
Wash raingear with detergents made for outdoor clothing, and apply a DWR treatment before wet trips.
Go easy on the apparel.
Dress lightly to prevent excess sweating and open vents wide.