Choose a technique you've been meaning to improve. Break it down into smaller components, dedicate focused training time, and seek guidance from coaches or online resources. Track progress and adjust as needed.

Below are some suggestions on techniques you could focus on for your current BJJ belt level: 

White to Blue Belt

1. Basic Guard Pass (e.g., Knee Slice Pass) - Understanding how to effectively pass the guard is fundamental. The knee slice pass is versatile and teaches principles of balance, pressure, and guard manipulation.
2. Rear Naked Choke - A foundational submission from the back. Learning this choke emphasizes the importance of back control, one of the most dominant positions in BJJ.

Blue to Purple Belt

1. Triangle Choke from Guard - This technique helps develop an offensive guard game. It requires timing, understanding of angles, and the ability to use legs effectively.
2. Sweep from Guard (e.g., Scissor Sweep) - A fundamental sweep that teaches mechanics and timing. Mastering sweeps from the guard is crucial for a well-rounded game.

Purple to Brown Belt

1. Leg Locks (e.g., Straight Ankle Lock) - Introduction to the leg lock game, an increasingly important aspect of modern BJJ. Understanding leg entanglements and submissions like the straight ankle lock is essential.
2. Passing Complex Guards (e.g., Spider Guard Pass) - Developing skills to pass more advanced and complex guards, adapting to various guard styles and learning to control the pace of the match.

Brown to Black Belt

1. Advanced Guard Playing (e.g., Berimbolo or De La Riva Guard) - Mastery of advanced guards shows a deep understanding of BJJ mechanics and strategy.
2. Systematic Approach to Positions/Submissions (e.g., Kimura Trap System) - Developing a systematic approach to certain positions or submissions indicates a high level of understanding and the ability to chain techniques effectively.

For each belt level, these techniques represent fundamental skills that build upon each other, reflecting the practitioner’s growing understanding and proficiency in BJJ. Mastery of these techniques not only prepares one for the next belt but also ensures a well-rounded skill set.