The first thing you have to realize if you're PLD is you have the worst enmity generation out of the three tanks by a moderate margin.


Having realize that, now you have to get used to OP people ripping agro off of you. It will happen, even if in high levels.

The thing that you have to get used to is effective tanking.

By your pull with shield lob, you will establish a decent agro on the single mob. Then, you will flash 2 times to get a lead on mob's agro. Then focus on the highest DPS' target and slam away your Rage of Halone. Selectively, you can also cycle through enemies and Rage of Halone each one if you think you have enough agro. Watch your agro meter (i'm assuming you know what this is.)

So, your rotation is not the problem.

The trick that I use when I'm PLD is this:

If (DPS agro on target is more than 50% AND target has more than 25%~ HP left), Rage of Halone and Flash once.
If (DPS agro on target is more than 50% AND target has less than 25%~ HP left), Flash once OR Shield Bash (if target can be stunned).
If (DPS agro on target is less than 50% AND target has more than 25%~ HP left), Rage of Halone OR flash once.
If (DPS agro on target is less than 50% AND target has less than 25%~ HP left), switch target.

The numbers and percentages depend on two things:

a) Your enmity generation.
b) DPS.

If your enmity generation is good, you can let DPS pummel a target more time while you establish agro on a different target.
If your DPS is good, you need to Rage of Halone at least 2 times then the target's HP will hopefully be less than 25%~. If not, refer to rules above.

That's the trick. But the technique to pull this off needs experience. Even high level PLD can mess things up. So, take your time and practice.

Effective tanking means to take hits and not let other people take the hits and not to stay at full agro ALL THE TIME. This needs some getting used to. In simple words: If the target is hitting you, even if the DPS is quickly climbing the agro table, it still means you're doing effective tanking.

One of the secrets of PLD tanking is Shield Bash. Shield Bash is the only stun other than Holy that can stun a target for a solid 12 seconds (if you spam it correctly). That's 12 seconds of the target doing NOTHING.

In under 12 seconds, hopefully you don't need that agro anymore and the mob will be dead. Dead targets can't have agro. Because it's dead.

Once you get your Shield Oath, it'll be better and agro generation will be doubled. At least, until you hit lvl 51.

My tip on early PLD Sword Oath tanking is this:

Don't be afraid to mark. Most DPS will respect the Mark, with a capital M. This greatly simplifies things as you can focus only one target.
If your DPS is attacking two things at a time, flash is the key until the target is dying. After that? Refer the rules above.
DPS is AOEing things down? Spam flash until out of mana then proceed to Riot Blade. (But mobs will probably be dead before you pull off a Riot Blade. Hopefully.)

Your weapon needs to be at the highest level. It's not that it would change the rules above, but it will greatly increase your enmity generation and DPS, allowing you to hit that Golden Rule of (DPS enmity at less than 50% and has less than 25%~ HP) allowing you to switch target.

Good luck and may the light be with you.