If you are joining a trapper team, make sure you have traps, at least the 3 non-elite offensive traps: Barbed Trap, Dust Trap, and Flame Trap. If you don't have these 3, chances are you aren't going to be contributing much to the team. Hand-in-hand with having traps is having a decent Wilderness Survival - I have mine at 13 when trapping.
Before you enter the UW, let the rest of your party know what other skills you plan on bringing - specifically what spirits or conditioners you are packing, and make sure no one objects or is bringing the same thing. I've had people packing Frozen Soil down there.

Here is a list of skills that should be brought by 1 person in the group (meaning someone has one of these skills, not that 1 person brings them all)
>Throw Dirt (for when the Aatxes get unruly)
>Poison Arrow (not necessary, but can help with smites that slip by traps)
>Healing Spring
>Favorable Winds
>Quickening Zephyr ~AND~
>Energizing Wind
To get the max amount of traps set, you need to have QZ AND EW active while setting traps. Serpent's Quickness can boost this even more, and IMO should be brought by everyone.
Make sure there is a designated leader/puller, and do what they do (except of course when they go to pull). The UW is not the place to bicker and argue about who got who killed, and usually if someone dies it's because more than 1 person is trying to lead. I don't know how many times I will start laying traps down, and some fool thinks he has a better place to lay traps and draws the rest of the damn party with him. It doesn't matter if the leader is doing it differently than you are used to - pick a leader and stick to it.
Never talk to any NPCs unless the leader has given the OK. Never accept ANY quests unless the leader has told you to, and ONLY accept the quests the leader specifies. I don't know why this seems so hard to people, but 90% of the UW jaunts I have been on that have failed are because some moron accepts all the quests from the first Reaper.
The best way to set up traps is to first have a clear idea of the area you are going to be pulling the mobs through. We'll take for example the first staircase. OK, you want the stairs themselves trapped, and you want to put the spirits at the bottom of the staircase. The idea is to have the aatxes see the spirits and have to charge through all the traps before they can attack them. I see people planting traps and wandering all over the stairs - this isn't necessary and increases the chances of an early aggro. The best way to trap is to have everyone spread out on the stairs, and lay all your traps on the spot you are standing. Just stand there and pump out the traps as fast as you can. Now, while you are doing this, be aware that soon the leader will be running off to pull mobs. You can keep laying traps while the leader is out there, but the moment you see the leader coming back, you need to move out. You should be back behind the spirits before the leader is. This is very important, and often overlooked. If the leader is trying to pull the mobs into the traps and one mob sees you there still laying traps, that mob usually breaks off from chasing the leader and goes for you. Suddenly you have one mob setting off all the traps while the other mob barely gets scratched, and that can spell doom for everyone.
That reminds me, my preferred Trapping Group is 7 Trappers and a Nuker. It's an easy ride for the nuker, as they are really only needed for damage control when the computer tries to get squirrely on you. The nuker should be ready with Meteor Storm in case for some reason or other a mob gets through the traps without much damage.
When it comes to smites, it is really important that once the leader is out rounding them up, all the rest of you are back behind the kill zone. Smites are notorious for 1 or 2 splitting off from the leader and running toward someone still laying traps. That 1 smite sets off all the traps, and what do you know? 5 more smites are coming, with no traps to hinder them.
Rounding up smites is an art in itself, and if done right can be beautiful. Done wrong, and you have a dead leader and/or total party kill. As a leader, what your objective is here is to get the smites as closely bunched together as you can, without dying and without the smites surrounding you. Once you have them all falling over each other trying to get you, THEN you lead them back to the kill zone like the Pied Piper. If they are all bunched up and haven't seen someone else and split off, chances are they will all die instantly once they hit the zone.
Another thing to remember is that some of the enemies in the UW are ranged attackers/spellcasters, like the Dryders and Coldfire Nights. To kill these with traps, you have to run far back from the kill zone. Practice makes perfect to know exactly how far, but it can be setup perfect so that the mobs reach their "stop and shoot" range right on top of the kill zone. Yes, it can be tempting to start shooting at them, but at the very least wait until the traps have all gone off. If you see the mobs are still marching towards you after the traps have started blowing, go ahead and shoot. Oh, that reminds me of another thing: if you are fighting spellcasters and they cast Meteor Storm on your location, for god's sake MOVE! Don't be like the AI and just sit in the shit with your pants around your ankles. It takes like 2 seconds to move out of the storm and resume firing.
Whew it's like 4:30 am, I gotta get to bed. I hope this helps some people, and if anyone has more to add please do so. Happy Hunting!
