(Innate): Darius' basic attacks and damaging abilities cause enemies to bleed for 12 / 15 / 18 / 21 / 24 / 27 / 30 / 33 / 36 (+0.4 per bonus attack damage) magic damage over 5 seconds, stacking up to 5 times.
Darius gains 5% movement speed for each bleeding enemy champion

This skill is Passive of Darius, This skill is Important to Noxian Guillotine,Try Stacking up to 5 stacks So your Ultimate deals additional Damage.

(Active): Darius deals physical damage to all nearby enemies in a circle around him. Champions in the outer half of the ability are struck by the blade, taking 50% additional damage.

This skill is your Main damage skill/Bread and Butter skill,Use this in harrasing and poking some enemies,Remember the range of this skill is just short.,Here is the example..
Dont spam this skill if you dont know that the champion will hit or not..

(Active): Darius' next basic attack deals additional damage and slows the target's movement and attack speed for 2 seconds.
Crippling strike's base cooldown is reduced by 1 second for each stack of Hemorrhage on the target.

This skill is One of your combo breaker,Do The Combo!, Apprehend> Crippling Strike> DecimateNoxian Guillotine> Apprehend(When escaping)> Ignite,When Needed.

Remember:This skill has 125 range .
(Passive): Darius Gain Some Armor Penetration
spaaaaaaace(Active): Darius Pull all enemies in front on him..

This skill is important to all Darius players,Save this when an ally will gank,When the enemy tries to escape,Strike him with Crippling Strike and pull him with an Apprehend..(From:Phreak)

(Active): Darius leaps to target enemy champion and strikes a lethal blow, dealing true damage. For each stack of Hemorrhage on the target, Noxian Guillotine deals an additional 20% damage.

The cooldown is refreshed if Noxian Guillotine kills the target, or if the target dies within 0.5 seconds after use

This skill is your last hitting skill,Save this when an enemy has low HP or when ganking,Remember,This skills deals true damage which means ignores Armour or Magic Resist.Means You Dont need to click the HP of the enemy to know the HP of that champion to execute them easily