Rhythm exercise
Although the following exercise is notated for a bass guitar (in the bass clef), it's all about displacing rhythms and notes.
The exercise takes a single note on each beat for every string and then it shifts it across one 16th note at a time. You can use this exercise in conjunction with your own instrument or voice, or you could take this exercise and turn it into a clapping exercise.
Transposing this exericse for voice or instrument is relatively simple. Just choose four different notes replacing each bass string (whether this is an open electric guitar string, a vocalised note or even brass or string instruments). Tap your feet or speak out loud the 16th note subdivisions of each beat so you have a backbone to practice too. If you have or use a metronome then this will be improve your practice further.
Turning the exercise into a clapping exercise
To turn this exercise into a clapping exericse, replace each note for a clap and each muted note (x) for a count (which could be either spoken out loud or tapped with your foot). Once again, using a metronome will help greatly if you have access to one.
Take the exercise slowly at first, breaking it down bar by bar at 60BPM.
Once you get used to the exercise, you can piece it together as one continuous exercise.
Now you can experiment with different tempos and tailor the exercise to match your needs and skill level.
Notice that the exercise finishes with each note on the third 16th note of each beat. Once you're feeling up to the challenge, you can shift each note one 16th note to complete the exercise (each note/clap will be on the fourth 16th note of each beat).