Two bards in a
party. Stand fairly close to one another (distance depends on the level of your skill). You can move away once the dance is cast.
- first bard, cast a tambour (guard tambour, mana tambour, or hit march)
- second bard, cast the dance (he can then cast another tambour, different from the one the first bard cast)
Some reasons the dance stops/can't be started:
- bards are not in same party
- bards are too far apart
- dancing bard spammed his dance skill (it will go on then off again

)
- first bard's tambour goes off (out of mana, hit by mob, recast tambour

)
- second bard gets hit by a mob/runs out of mana, his tambour/dance goes off, cast the dance again
- second bard casts same tambour as first bard did, dance will not work

Make sure you level up your passives that keep the dances up.

Tripping and Screen Dance, I think they are called.
Hope this helps.