Looking for a BLM guide

[Friske]

There's a thread where someone posted a very useful 'BLM Resources' guide that includes a calculator for damage as well. It's somewhere here, you should be able to find it.
About macros. I personally don't really use many macros for blm, since firestarter procs are random and can't be automated. You could, however, try to make a few macros like thunder2 to fire 3 to start your rotation. The BLM rotation is mostly fire1 spam anyway.
Surecast is a very niche ability, and is hardly ever used against your common monster. ButI I've heard some people using surecast to prevent their LB from being interrupted. And you can also use it for spells like flare, to secure a guaranteed attack. But overall? Not really used that much.
Manaward is very useful if used correctly. It's mostly used on bosses such as garuda/ifrit/titan when they're using their magic abilities. Eg. Tumolt (stomps) damage can be slightly mitigated with manaward. Ifrit's Hellfire after the nail phase can be mitigated as well. So overall, it really depends on the boss fight.
Black mages have very little choice when it comes to Xclass abilities, since the only useful ones are arguably Raging strikes, quelling strikes, Eye for an Eye, Physick and Virus. Raging strikes and quelling strikes are probably going to be your most useful ones, while the rest of the abilities are more to do with support.