Recipe
Tanky body armour
Recommended method
Greater Essence craft
Transmute to Magic, then Greater Essence of the Body guarantees +# to maximum Life as you go Rare. Fill the rest with Greater Exalted Orbs.
For the highest tiers here, craft on an item level 82+ base. Lower item levels still work but cap the rolls.
Mid-game plan: this uses Greater-tier currencies/essences for stronger rolls. Switch to Endgame for Perfect-tier (best-in-slot).
Step-by-step
Get the base
Find a Warlord Cuirass (Body Armour) at item level 82+ so the best tiers are available.
Quality it first
Use Armourer's Scrap to bring the Warlord Cuirass to 20% quality before crafting.
Transmute to Magic
Use a Greater Orb of Transmutation on the white base — it becomes a Magic item (these essences are used on Magic items).
Use Greater Essence of the Body
Use Greater Essence of the Body on the Magic item — it becomes Rare with a guaranteed +# to maximum Life.
Exalt for +#% to Fire Resistance
Use a Greater Exalted Orb with an Omen of Dextral Exaltation (suffix only) to add +#% to Fire Resistance.
Exalt for +#% to Lightning Resistance
Use a Greater Exalted Orb with an Omen of Dextral Exaltation (suffix only) 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.