The Force Sensitive is the first rank in the Sith Order. These are people who are seeking an understanding of the dark side of the force.
To become a Force Sensitive you must join the Roblox group.

The Sith Hopeful has taken steps to learn the dark side of the force. They are ready to prove themselves worthy of training.
To become a Sith Hopeful you must pass 3 of any types of training.

The Sith Apprentice is one fully devoted to the study of the dark side of the force. They study under a Sith Lord + and must learn the curriculum associated with the apprentice program.
To become a Sith Apprentice a Lord+ must take you as their apprentice.

After passing their Sith Trials, a Sith Apprentice may elect to study the mysteries of the force. After studying and completing an assessment on the Sith Sorcerer curriculum, the Sith Sorcerer must prove their knowledge through service to the Sith Order.
To Become a Sith Sorcerer you must pass Sith Sorcerer Assessment, the curriculum for those can be found on the Sith Curriculum Page.

After passing their Sith Trials, a Sith Apprentice may elect to follow the path of the Marauder. Focusing on the strength of saber combat as well as the mysteries of the force, the Sith Marauder is the perfect balance of saber skill and understanding of the force.
To Become a Sith Marauder you must pass Sith Marauder Assessment, the curriculum for those can be found on the Sith Curriculum Page.

After passing their Sith Trials, a Sith Apprentice may elect to follow the path of the Juggernaut. The Juggernaut is the frontline defense of the Sith Order. They are experts at melee combat in defense of our order.
To Become a Sith Juggernaut you must pass Sith Juggernaut Assessment, the curriculum for those can be found on the Sith Curriculum Page.

These are members who have completed their advanced study requirements. They are equipped to train the next generation of Sith in the dark side of the force. They take direction from the Dark Council on how to deal with their apprentices. The Sith Lord is the first of the ranks that is responsible for enforcing the rules of the order. Sith Lords may have up to 2 apprentices at a time unless given permission by the Dark Council or Emperor to have more.
To become a Sith Lord you must get 3 Approvals from Dark Council+.

A Darth is a Sith Lord who has proved their usefulness to the Dark Council. Through their service to the Sith, they are granted the title of Darth. They are the group of people that the Dark Council chooses their new members from. They are the main enforcers of the Rule of Law and report directly to the Dark Council.
To become a Darth you must pass a Dark Council Vote.

A Dark Councilor is someone who has been appointed by the Emperor or Dark Council to help run the Sith Order. They are the rule makers of the order. They may be appointed by a ⅔ vote of the Dark Council or by direct appointment from the Emperor. There shall be no more than 12 members on the Dark Council at any point. This includes the Emperor’s Hand and Wrath.
Pass a 2/3 Dark Council vote/

The Emperor’s Hand is a member of the Dark Council that represents the Emperor within the Sith Order. They help run the Dark Council in the Emperor’s absence. They are responsible for making sure that the Sith Order is following the Rule of Law and that the Dark Council is following the will of the Emperor. They are appointed directly by the Emperor. 

The Emperor’s Wrath is a member of the Dark Council that represents the Emperor outside of the Sith Order. They represent the wrath of the Emperor and are responsible for dealing out the Emperor’s will in the wider galaxy. Their word is as good as the Emperor’s unless contradicted by the Emperor himself. They are hand selected by the Emperor to make sure that their will is known and respected by the galaxy. 

The Emperor is appointed by Askavix to lead the Sith Order. They have absolute control over the Sith Order but often delegate their work to the Dark Council, Hand, and Wrath. The Emperor has the final say on any Dark Council action and has the power to change the Rule of Law at his will.