Play hip hop music on speakers. Practice moving different parts of your body to the beat. For example, move only your hips in a side-to-side motion to the beat of the music. This exercise trains the body to move to a beat.
Practice freezing. Freezing accentuates the beat of the music by incorporating stillness in the movement phrase. Continue the exercise of moving to the music, but put long pauses in between. Move on 1 and 2, then be still for 5, 6, 7 and move again on 8.
Combine the rhythm and freezing exercises simultaneously in different parts of the body. Move your hips and hands at the same time. Add the head. Find out how many different parts of the body can move at once.
Watch other hip hop dancers to find out what they do. Go to nightclubs, and stand in the cipher (dance circle) to watch the dancers battle. Imitate their moves as much as you can.
Ask dancers you admire to demonstrate difficult moves. Most hip hop dancers are happy for a chance to teach their skills.
Step into the hip hop circle and battle. The only way to learn is to do. Push your skill limits by trying new steps and dancing with people who are better than you. Keep this up, and watch the improvement.