The way this Build works is that you'll increase your Arcane to make your Spells hit hard, and to boost the damage of your Weapon. You should use an Occult Affinity Weapon, with the Bloody Slash Skill, which scales with Arcane for maximum Bloody Slash damage, but you can use any Skill you want.

You need at least 25 Faith to use Golden Vow, and 23 to use certain Dragon Spells, so you can't have less than this. You'll use your Jellyfish Shield's ability: Contagious Fury to boost your Spell Damage and Weapon Damage, and Golden Vow to do the same. You can then chuck Lightning Spears or Black Flame balls at enemies or use Bloody Slash.

You'll use Agheel's Flame or Smarag's Glintstone Breath to take out enemies with larger health pools or Bosses, holding down R1 to cast the spell fully twice. This absolutely melts Bosses, especially when you are buffed with Contagious Fury and Golden Vow. Make sure to equip the Scorpion Charm that best suits the breath you intend to use.