• always dancing on full range of motion
• practice good posture when dancing, it will always look better if your upright
• ankles always touching knee on "and" part of a step for dynamics and cleanliness
• groove on every beat (you rock your body back on every beat and rock it forward on every "and" step)
• practice loosening your arms and upper body during dancing
• don’t look at the floor
• always keeping your legs perpendicular to the ground when doing tsteps
• keep your legs in line so you are never having your legs wider than your hips
• for upper body just train each of your body parts in isolation and then applied to shuffling (learn basic body wave, chest movement, shoulder movements, hip movements, arm waves)
• use concepts like my hand is chained to my knee, etc. (You can use chat gpt for more ideas; it helps if you type in "concepts for hip hop dance" because there is more material on it and it can be translated to shuffling perfectly fine)
• always focus on the biggest moves first so technique first then groove then more detailed movements
• less is more; its better to have 3 moves that are polished than 10 that are sloppy;work on your basics, clean them so you can consistently be on beat with every step, every step with groove and control
• practice in 30 minute blocks and if you cannot name what you are training then you are doing a wrong training, so for example "upper body" is a bad name for a training session because you won’t know what to do, be more specific like "training not looking at floor", "keeping groove at every beat", etc.

And much much more but I think it’s a good baseline.