Specify sheet margin. The default margin is 20 points. Specifying -m solely sets left margin to 40 points. For example -m 10 sets all margins to 10 points. 50l25bt30r set bottom and top margin to 25, left margin to 50 and right margin to 30 points.
Margins can have negative numbers.
Very large values have funny effects. This is left as an exercise to the user. Specify logical page margins. For syntax, see -m option. Margins can be negative.