Hi. Snagz here.

I'm going to share with you some things I've learned about bard along the way, some common misconceptions I had about the class, and my general experience along with tips and tricks that have helped me. First, here's some useful resources that have been instrumental in my success:

Bard BiS Options
My personal set (minus some minor variation)
Endgame Bard Guide by Krietor

Krietor's Bard guide is packed with useful information. So much so that there's no use for me reinventing the wheel. Instead, I'll break it down into layman's terms as best I can and summarize.

Your opener is critical. This is the part where everyone is frontloading cooldowns, buffs, vulnerabilities, that all stack and mesh with each other to make one big messy explosion that pushes the boss into that next phase as fast as humanly possible. This is the early-game, and it sets you up for success or failure in the rest of the fight. It's also important to get your opener down 100% reliably because it helps develop your "routine". I'm speaking mostly about buff sync. A Hawkeye'd auto-attack will do, say, 10% extra damage for example. A blood-for-blooded hawkeye'd auto-attack will do (again for example) 25% extra damage. By syncing b4b with hawkeye, you've improved the effectiveness of both hawkeye and b4b instead of using them individually. Throw in a barrage and you've just tripled/quadrupled the effectiveness. You can see how stacking adds up. (Also, if you use the opener in Krietor's guide, you'll see that your timings sync up to that exact same buff stacking I just referenced and use it in every fight.)

Skill priorities. We bards have a lot of cooldowns and oGCD's to juggle. This is great for burst, but a pain in the ass for micro-management. It helps to always have a priority system in your head. Krietor's guide goes into detail, I'll sum it up here:

1. Straight Shot -> Windbite -> Venomous Bite. Always use these in succession, unless you proc a straighter shot and need to conserve the TP and have sufficient duration left on the SS buff and are comfortable with off-setting the timer.
2. Bloodletter. Ideally you are spam-mashing this in between your GCD abilities. This is a significant portion of your DPS.
3. Straighter Shot. Use this proc instead of heavy shot when available.
4. Flaming Arrow.
5. Repelling/Blunt. Use these as allowed between oGCD when you don't have BL procs.

Most importantly, know the fights. The more experience you have with a fight, the more you learn the pace, and get a "feel" for it. If the boss is going to jump in 5 seconds but all your CDs just lined up - hold off on them until he lands. If blight is going to keep you from attacking halfway through your opener, delay the whole thing, just put up dots and trudge along until a good burn phase. The more you repeat fights, the more you know when to put up songs during downtime, when your buffs will come back up, and how long you need to sing to get you through that add phase rotating dots without going OOTP.

This has been a giant wall of text.
tl;dr Message Snagz in-game or on the forums here if you have any questions.