The only thing I never did in terms of power slaying was use a cannon. I didn't want slayer to be a profitless powerlevel for me. If you want xp, definitely use a cannon, if you want money, hold off on the cannon a bit (I'd still cannon things like Bloodvelds and dags though, just because the xp is too good to pass up for those :P)

 

I would definitely recommend using piety/turmoil on tasks though, and when ever possible, use your best combat familiar to help you kill monsters. Use Super pots on every task, and once you get them, extreme pots

 

Buy armor sets like Verac, karil, pros, and eventually bandos. Go for the Soul Wars cape ASAP if you don't already have one. Fury, berserker ring, full slayer helm, rune defender (Never DFS, it's only good for one monster)

 

pretty much it's all been covered.

You don't need veracs for slaying.

You don't NEED a slayer helm either, but it's usefull.

Ah yes the DFS. It's pretty useless imo. Most slayers use them but I think it's a waste of the +19 attack bonus you could have with a rune defender, which is extremely helpful. DFS may have +2 strength more and a lot of defence, but I prefer owning monsters faster than getting hit less - that's what healing familiars are for right?

 

Also like others have said, the soul wars cape is very very handy. I used to wear a 99 cape, but now always wear soul wars cape in tasks which require prayer as it's +8 more than a 99 cape which is basically like another prosylete platebody.

 

Super antifires + Chaotic Rapier if you have one or Z spear if you don't, for metal dragon tasks it is a must have for efficient slayers (not to mention it's fun pwning them :D)

 

I think that's everything pretty much covered now