Elden Ring is a pretty rough game, full of challenges and enemies that would make even the most steadfast of Tibetan monks lose their cool. However, the game also has a host of ways you can face these challenges, and you can even change strategy just by visiting a Site of Grace. One of those ways is by using incantations, which are the cheapest and most useful ways to get ahead in Elden Ring.
Weapon incantations
Black Flame Blade
Order’s Blade
Bloodflame Blade
Electrify Armament
Poison Armament

Weapon incantations are useful for invoking a specific effect that can help you in a fight without having to use Ashes of War or effects that don't scale well with your character. They’re inexpensive, don’t cost tons of points or mana and are a great way to enhance weapons with normal Dexterity or Strength scaling. They also have interesting effects, like the Order’s Blade, which can kill enemies who are resurrected without needing to hit them on the ground.
Catch Flame / O, Flame!

The two basic fire incantations only require 8/16 Faith respectively and cost barely any mana. They can do striking damage and can be thrown one after the other without wasting any time. Their only downside is their attack range.
Flame, Grant Me Strength / Golden Vow

These incantations enhance damage, while Golden Vow also boosts defence powers during combat. They require a higher investment of Faith, 15 and 25 each. However, they’re an excellent asset for all characters. The first one increases both physical and fire damage, while the second one enhances all damage you cause. This can be combined with other items for increasing damage such as talismans or the Vial of Miraculous Salvation to exponentially increase the damage from a multitude of weapons, spells and other incantations.
Bestial incantations
Bestial Constitution
Bestial Vitality
Stone of Gunrraq
Bestial Sling

These incantations are particularly cheap, costing a measly 9/12/10/13 Faith respectively. The first two are improvements you can use both at the beginning and in the middle of a fight. Bestial Vitality will gradually heal you over time while Bestial Constitution protects you against bleeding and freezing, two of the most destructive effects of the game.
The other two are fight incantations: cheap to use, quick to throw and able to cause a lot of damage to the enemy's posture. These are also incantations that cause physical damage and with a difference: they scale with Strength so they’re ideal if you want to improve the rank of that character that’s strongly inspired by Conan the Barbarian.
Flame, Cleanse Me

A very useful incantation depending on what part of the game you're playing. These incantations are usually the most difficult, and for 12 Faith they’ll remove all traces of poison and scarlet rot.
Rotten Breath / Swarm of Flies

15/11 Faith and 12/16 Arcane—commonly used in Bleed Builds—will get you these two incantations. The first one induces scarlet rot on enemies, causing huge and very long-lasting damage, particularly in weakened areas. The second one sends vicious flies to inflict blood loss on opponents.
Pest Threads

You’ll have suffered this incantation from those odious enemies that look like centipedes and like rot. It’s a thread attack that deals a lot of damage to targets, has an absurd reach and is very cheap both in terms of mana and Faith, costing only 11 points.