Discuss with the director and DP how in-depth they want the storyboards. Some won't care if stick figures are drawn, so long as the general makeup of the shot remains in tact. Others want dynamite sketches.
If the answer to Step 1 is more dynamite, get all headshots of actors in the scene.
Using the shot diagram as well as instructions from the decision making parties themselves, begin a series of comic book-like sketches translating text into pictures.
On these drawings, add in subtle notes such as "Push In" or "Static," so those viewing will know the difference in styles of shots.
Do not, however, draw every shot as it will appear on screen. As in, if you start with a Close-up on Character A, cut to a wide shot and then back to CU on Character A--you don't need to draw that second close-up. It's the same shot as the first one, just edited creatively.
Meet with the director to approve, and if you get the green light and he wants everything in-depth, go back and add in scenery or landscape structure to make the most accurate portrayals as possible.
This isn't always necessary, as some directors merely want pictorial representations as a means of determining what they need to cover, but erring on the side of caution is always a best bet.