All the PostScript hardcopy commands use the variables ps-lpr-command and ps-lpr-switches to specify how to print the output. ps-lpr-command specifies the command name to run, ps-lpr-switches specifies command line options to use, and ps-printer-name specifies the printer. If you don't set the first two variables yourself, they take their initial values from lpr-command and lpr-switches. If ps-printer-name is nil, printer-name is used.
The variable ps-print-header controls whether these commands add header lines to each page--set it to nil to turn headers off.
If your printer doesn't support colors, you should turn off color processing by setting ps-print-color-p to nil. By default, if the display supports colors, Emacs produces hardcopy output with color information; on black-and-white printers, colors are emulated with shades of gray. This might produce illegible output, even if your screen colors only use shades of gray.
By default, PostScript printing ignores the background colors of the faces, unless the variable ps-use-face-background is non-nil. This is to avoid unwanted interference with the zebra stripes and background image/text.
The variable ps-paper-type specifies which size of paper to format for; legitimate values include a4, a3, a4small, b4, b5, executive, ledger, legal, letter, letter-small, statement, tabloid. The default is letter. You can define additional paper sizes by changing the variable ps-page-dimensions-database.
The variable ps-landscape-mode specifies the orientation of printing on the page. The default is nil, which stands for "portrait" mode. Any non-nil value specifies "landscape" mode.
The variable ps-number-of-columns specifies the number of columns; it takes effect in both landscape and portrait mode. The default is 1.
The variable ps-font-family specifies which font family to use for printing ordinary text. Legitimate values include Courier, Helvetica, NewCenturySchlbk, Palatino and Times. The variable ps-font-size specifies the size of the font for ordinary text. It defaults to 8.5 points.
Many other customization variables for these commands are defined and described in the Lisp file ps-print.el.