A whole-step (or whole tone) comprises two half-steps. On the keyboard, whole-steps are formed by the two outer keys in a series of three, adjacent keys. Most often we think of the whole-steps formed by two white keys with an intervening black key (W-B-W), but each of the other possible three-key patterns (W-W-B, B-W-W, B-W-B) also outlines a whole-step. To spell a whole-step above a given note, go up a chromatic half-step and then up a diatonic half-step or up a diatonic half-step and then up a chromatic half-step (whichever is easier):
Drill and Practice: Whole-Steps
Drill and Practice: Half-Steps and Whole-Steps