If you don't party alot (=pre Mediah), you can focus on your damage skills first.
Gear
Until you get to boss armor, focus on getting a full Grunil +15 set.
Of course, PRI or DUO would be even better.
Main weapon: Kzarka, Liverto or Yuria Staff
Offhand/secondary : Nouver or Steel Dagger
Accessories
Like all classes, try to get at least
- Necklace: Ogre Ring, or Scarla Necklace (has both AP and DP)
- Rings: DUO Blue Coral ring (for the MP) or PRI Mark of Shadow (no effect)
- Earrings: PRI Witch's Earring (no effect)
- Belt: PRI Tree Spirit Belt (has accuracy but you don't really need that)
This cuts down your AP, but it will give you DP back for it. If you solo alot, even in Mediah or even Valencia, you might consider getting this.
However, I think you'll be just fine with more AP. Especially when you get your boss armor, you'll also lose the Grunil AP bonus so trading more AP for more DP may not be the best choice here.
When you get to the point where you have your boss set, you can work on getting your accessories up as well.
It doesn't stop there

Priority / Combo's
Basics
- Magical Evasion (Shift + A/S/D OR W+W): Your dodge. Get it maxed. No questions asked!
- Earth's Response (A+LMB or D+RMB): Dodge with damage! Too bad you can't spam this :/
- Magical Shield (Q/quickslot): Want to live? Get this.
- Spellbound Heart (quickslot): Gives you mana over time, after it expires you can just cast it again. This will be a huge help when you're busy healing people in groups, or when you're too busy keeping yourself alive. Not many people max this, I do. And I'm very glad I did!
- Mana Absorption (Shift + LMB): Casting for your life and low on mana? Yes we all know this problem... Max this ASAP
- Mind Training (passive): This shit increases your casting speed. You'll want this at least one row. It's not prio however, how many you take of this is up to you. You can also choose to get casting speed crystals instead (or, you know, both?).
- Infinite Mastery (passive): OMG THIS SHIT GIVES HP. Should say enough for one of the most squichy classes... MAX IT!
- Healing Aura (E/quickslot): Heals you. You'll need it, even if you don't group. Part of your self-sustain.
- Chain Lightning (Shift + RMB): This will be your main damage when soloing.
- Lightning Storm (LMB + RMB after ^): This follow up does alot of damage and slows down enemies.
- Lightning (S + F, 100% skill): This is also one of the skills you'll be using the most.
- Residual Lightning (RMB after ^): This skill does alot of damage, so if you use Lightning alot, be sure to use this follow up!
- Fireball (S + LMB): Since this is a max. 4 target skill, you won't be using it as much as the lightning skills. However, this DOES inflict knockdown, so it's the perfect skill to buy you time when mobs get too close.
- Fireball Explosion (RMB after ^): As the fireball already gives you knockdown, you won't really need this. But it does do alot of damage, burns enemies and knocks them down as well.
This is where you'll start going in groups. As the supportive witch you'll need healing. If you're a smart witch, you already have one of them maxed out.
- Frigid Fog (S+Q): One of your "panic" skills. You're busy supporting your group. If shit comes too close and you can't dodge for whatever reason, cast this and run back to your tank or dps.
- Healing Lighthouse (Shift+E/quickslot): The biggest healing skill you'll ever get. You can heal your entire group with this, as long as they stand in the radius. Get it maxed up. You also get your mana back with this. However, take caution when casting because you're unable to move from the spot. A good tank will make sure they got the mobs so you won't take aggro.
- Blizzard (Shift+LMB+RMB): Big fat damage!!! If your group does their job and you don't have to heal them as often, you can decide to use this skill. It does an amazing job on damage, but you'll be unable to move while casting. You WILL however get "forward guard" (so, protection on front) when casting. You can cast this until you run out of mana. So be sure to combine this skill with at least Spellbound Heart, and cast Mana Absorption right after.
- Resurrection (quickslot): Resurrects one of your party members. BUT... It's a pain casting it, you can't be interrupted (so most people choose to respawn on Town/Node instead), YOU DON'T SEE THE BODY... AND you need to click ctrl while pointing on the body in order for it to work! So yeah, unless you really have extra points, or feel like you should max this... Ignore it. You get one for free anyways.
- Magic Lighthouse (quickslot): "Summons a magical object that attracts enemy attention. Enemy DP-10 for 10 sec. Lasts 20 sec." No. Just no. You can use these points much better in some other skill. I've tested the difference with I, II and III and imo its really not worth getting. As far as I'm concerned, this skill doesn't even work (it's supposed to be some kind of taunt but you aggro over it way too fast).
- Skilled Hunter (passive): Yay monster AP! No. Just no. Again, if you're willing to spend points in this then be my guest, but I'd rather go for a more damaging skill than something that's PVE only.
- Protected Area (Shift+Q): Optional. So far I've only used it with scroll bosses and now that I've awakened my witch I'm not even using it anymore. You get one for free, just leave it at that.
- Earthquake (Shift+F): Can be fun sometimes, but you'll mostly be casting lightning skills and in groups you'll focus on healing/supporting more so just ignore this. You get one for free, leave it at that.
- Speed Spell (quickslot): This CAN be a "panic skill" if you decide to use it. It greatly increases your attack speed, movement speed and casting speed. I've only used this during tough fights (when your tank/dps pulls too much and decides to almost die dispite your healing efforts) or scroll bosses. The first one should be enough, imo.
- Freeze (S+E): Damage sucks, it can only target 2 enemies and it gives freezing. Yay. I'd much rather cast Frigid Fog or Blizzard in that case. Ignore this skill.
- Teleport (Shift+Space): Optional. I didn't use it as much, only when I had to run as fuck. But then again, that was just panicking, because I could as well go for my panic skills instead. It doesn't add much imo. Up to you what you do with it.
- Dagger Stab (F/quickslot): Melee. Single target. Much nope. Unless you like PVP, you know, a little stab when they come too close
- Magic Arrow: If you have the points, why not. Multiple Magic Arrows can actually be quite fun (though it's quickslot ony), just not really for a supportive witch...
- Concentrated Magic Arrow (LMB+RMB charge): Nope. Fireball much better!
- Sage's Memory (quickslot): "All Casting actions ignored for 15 sec." Spam skill. You get instant cd. However if you have long casting times, this is really useless. Can be a nice "panic" skill though. I didn't use it much.
Read the above recommendations to figure out what you should build!

Add-ons
This is what I took, but what you should get really depends on what skills you like to use the most.
You can't get an add-on for the healing/utility skills, sadly. So just take something you use alot.
The best options to add to is casting speed, defense and movement speed.
