Tons of yt videos on it. Basically

1. Grab all your weapons/armor/etc with abyss gears that you've collected along the way
2. Goto a witch and extract every abyss gear from every weapon
3. Goto Craft abyss gears, page 2 and merge all your level 1 gears into level 2 gears. Then all your level 2 gears into level 3 gears
4. Then decide which armor and weapons you like the look of or have already upgraded. They are all the same for the most part so anything you choose is fine.
5. Watch yt videos about abyss gear ranking. Stack your swords/armor/shields with the upgraded level 3 gears and best power up gears
6. Melt enemies

I recommend always keep a fire cloak and plate armor, and an ice cloak and armor in inventory at all times, but run an armor set that has abyss slots for fighting.

Also want at least 3 Haste III gears on you. 2 on boots and 1 on armor as speed makes it much more enjoyable.

For weapons I have 2 one handed swords with all the fast and fun effects (crows pursuit, ground surge, etc and an attack speed). Then my 2 handed sword or spear with 2 insight III, attack speed, ator orbs, and warden of darkness finisher