Intro to All Along The Watchtower
The intro features a pickup that begins on the "&" of beat 3. In other words, the first three notes of the song fall on "& 4 &." Counting the beginning of the song correctly is important because otherwise, the main drum beat that begins on bar 5 will have an odd placement.
Pickup: A partial measure, usually before the first full measure of a song.
Ideas for Exploration — Try singling out some of these measures and using them as a drum fill between your own beats. Then, try moving the rhythms around to different toms and cymbals to create new fills.