Recipe
Resistance-capping ring
Recommended method
Essence craft
Transmute to Magic, then Essence of Insulation guarantees +#% to Fire Resistance as you go Rare. Fill the rest with Exalted Orbs.
For the highest tiers here, craft on an item level 82+ base. Lower item levels still work but cap the rolls.
Step-by-step
Get the base
Find a Biostatic Ring (Ring) at item level 82+ so the best tiers are available.
Transmute to Magic
Use an Orb of Transmutation on the white base — it becomes a Magic item (these essences are used on Magic items).
Use Essence of Insulation
Use Essence of Insulation on the Magic item — it becomes Rare with a guaranteed +#% to Fire Resistance.
Exalt for +#% to Cold Resistance
Use an Exalted Orb to add +#% to Cold Resistance.
Exalt for +#% to Lightning Resistance
Use an Exalted Orb to add +#% to Lightning Resistance.
Divine to perfect
With the right mods on, use Divine Orbs to push their numeric rolls toward maximum.
Path of Exile 2 crafting is partly random. The odds and costs below are realistic estimates to set expectations — your results will vary roll to roll.