You can make your weapons the best weapons in Nightingale by infusing them. Weapons and gear with enchantments and infusions will deal significantly more damage, give you special buffs, and generally improve your stats. Here's how to infuse them!
NIGHTINGALE ENCHANTERS FOCUS GUIDE – Infusions Charms and Enchantments explained! How to use magic?
In order to use enchantments and infusions in your weapons and armor, you must first complete the Antiquarian Site of Power. After you do that, speak to Puck and enter a new realm. Complete the first trial for Aurelio to earn the Enchanter's Focus Table schematics (if you haven't already purchased them from the Trader like I did) and your first Infusion. You can build the Enchanter's Focus Table using the following materials (which means you'll first need a Saw Table and a Smelter):
From this point on, you can use the Enchanter's Focus table to craft Infusions and Enchantments.
Enchantments and infusions are crafted using Essence, Essence Dust, and some special items like Human Seals. You can unlock more recipes through the Essence Trader or Hope Echoes. You start with just a few recipes to get started.