First of all, it's easier when you go faster. Seriously - you can skip over the tops of some of the bumps and it smooths them out. If you hit one of those bumps where it drops away a few feet on the far side with some speed, you don't feel near the impact you do if you go up to it at a crawl and just drop to flat. (Picture the angle you're hitting the ground at.) Pick a good line with fewer bumps and go fast. It's less jarring.
Second - drop your downhill shoulder. It sets off a chain reaction in your body position, pushes your downhill knee in and sets your edge while keeping you in a relaxed body position. Use both your feet though - if your downhill ski goes, you want just enough pressure on the uphill one to be able to take over and recover.
Third - absorb with your legs when you're in the wavy bumps. Put some muscle into it and absorb and extend. Try and keep your upper body moving in a straight line with your legs pumping to absorb the bumps. It's work, but you get through it faster and you're just using some muscle energy, not stressing your back and joints.
Fourth - (this is not as much of a problem now as earlier in the season) But if you see small rocks in your path and can't just pick up one ski over it, the safest thing for your skis is to keep your speed up, stay light on your skis and go straight over it. If you try and scrub speed, freak out and avoid it, etc. - you have a MUCH greater chance of tearing up edges when you hit it sideways, or worse yet, cartwheeling down the bumps because you lost control doing a panic maneuver.
Finally, If you need to stop and rest, pick a line, or talk to others in your group - get off of the traverse and out of the way. Then look behind you before you start (also look behind you when you're on a traverse that merges with another traverse line). And look behind you if you careen up above the traverse into the powder and plan to drop right back onto it once you've recovered - someone may have been right behind you and stayed on the line. Traverse etiquette is basically no different that what you would do when driving a car on the highway.