It is really down to OSRS gold personal preference. Magic is the only real one which sticks out. Others can be trained far more readily in member places, anyway. I waited a long time before becoming a member because I thought my combat level and abilities weren't good enough for it to be well worth it. Membership really isn't a upgrade only for high levels, though. If you want to spend less, you could wait a bit, as freeplay still has things to offer. However, don't do it if you're going to start taking a look at the game as a chore for this. I'd just say that when freeplay isn't any more fun/as fun, gain membership.

Then cannon any activity that you think is worth it, also for ones you don't (or if you're like me and need combat XP), utilize piety with super collections and prayer potions, or whatever battle prayers you can use (which is the reason you utilize neitiznot/proselyte legs to your +prayer).

A routine slayer helm is Face Mask, Nose Peg, Spiny Helm, and Black Mask like arham said. To make it a complete slayer helm you will need to add a Focus Sight and a Hexcrest for your slayer helm. For your master, a general guideline for Slayer would be to simply use your best master, however if you'd like the quickest points you are able to do 9 tasks with Mazchena (sp?) , the demon guy in Canifis, and then do your 10th tasks together with your highest available master (Sumona+).

I will purchase the berserker ring and prayer fostering armor. I am only able to use the 15% attack and strength bonus prayer though, not yet chivalry or piety. Super potions are the reccomended thing afterward, right? I would like to train power, so you've all been stating d scim, SS, or korassi's (that I don't currently have). I've got the RFD gloves, but maybe not yet nez. Is black mask okay until full slayer helm? I will use earmuffs along with buy RS gold other head items rather until then also.