Macros take counts
Just like motions, q accepts a count. 3q replays the macro three times
back to back, 10q ten times, and so on.
That’s only useful if each replay ends up somewhere new, so the trick is to
record the move to the next line as part of the macro. A macro that edits
the line and then presses j will march down the buffer one line per
replay, and the count decides how far it marches.
Try it in the editor. Work through the checklist below. Record a macro
that puts - in front of the line and then moves down with j. Stop
recording, and press 3q to finish the other three lines.