This first exercise will introduce you to the concept of alternating the stressed note within a repeated phrase. As you can see, the exercise only uses five notes: C, D, E, F, and G. Therefore, there is no need to move your fingers throughout the exercise; your thumb should stay on C, your index finger should stay on D, and so on, with your pinky landing on G. When you begin this exercise, the initial temptation will be to accent the same note each time you repeat the phrase (in this case, the C); however, notice that the downbeat of the first measure is C, while measure 2 begins with D. Make sure to follow the music accurately; accent the notes that should be accented.
While practicing, always remember that it is important to use your fingers and not your arms to provide the power behind each keystroke. Your wrist should remain free and generally parallel with the tops of the keys. Another very important part of a good practice routine is the use of a metronome or drum machine. Not only does a metronome help you to play in perfect time, but it can also help to improve your internal sense of the beat. Also, unlearning a bad habit (such as playing out of time) is often more difficult than learning a concept correctly from the very beginning, so get off to the right start and save yourself some trouble in the future.
As with any exercise, start at a comfortable tempo; make sure you begin slowly enough that you can play the exercise perfectly, and then begin increasing the tempo at a steady pace. When you do increase the tempo, make sure you can play the exercise perfectly at the new tempo before increasing it further. Also, you can practice this accent exercise even when you do not have a keyboard around; mimic the finger movements on your knee (still doing the accents) or a tabletop, or just about anywhere!
As with any of the exercises, if there is only one line shown, make sure to practice the exercise with each hand individually and then with both hands together. When using both hands, first try playing the line in octaves, and then play the line symmetrically, or in a mirror-like fashion. In other words, if you have both hands set over C through G, play the line that is written with the right hand, but play G, F, E, G, F, E, G, F, and so on, so that each hand is playing with the same fingerings.
Practice is the key. Shake your hands out really well when they begin to feel tired or tense. To do this, hold your arm down beside you and shake your hand until you feel the tension release.