The easiest way is to have a nice main melody, once you have that the rest goes easy, you just built everything around that even the drums, but you need playing skills for the main melody. Listen to some Danity Kane stuff and look at the main melodies how they are build and in what key they are, you can even try to replay them, like the melody from Ride For You. It's interesting when you find melodies in commercial songs and notice that the composer has used 1-2 notes that are not even in the scale.