Tip #1: PUGs are your last resort. Avoid them like the plague.

Here's the latest of Charabis's etiquette guides, covering that most-hated of all MMOG things, the Pick-Up Group! Join him as he takes a look at how not to become hated.

...It's all too common for someone to just grab everyone they
can get to fill out their group, without first figuring out how they
fit. This random assembly consistently leads to groups that will wind up
completely frustrated, and often bickering amongst themselves even while
the enemy pounds on their heads...

Check out the full guide at Ten Ton Hammer's G&H site.