18) How do I get METAFONT to do what I want it to do?

    METAFONT allows you to create your own fonts, and ordinary TeX users
    will never need to use it. METAFONT, unlike TeX, requires some 
    customization. Each output device for which you will be generating 
    fonts needs a mode associated with it. Modes are defined using the 
    mode_def convention described on page 94 of _The METAFONTbook_. So 
    first create a file, which we will call local.mf, containing all the 
    mode_defs you will be using. The file modes.mf by Karl Berry,
    available via anonymous ftp from ftp.cs.umb.edu (192.12.26.23) in
    ./pub/tex is a good starting point for this. Listings of settings for 
    various output devices are also published periodically in TUGboat 
    (see question 11). Now create a plain base file using inimf, plain.mf, 
    and local.mf:
       % inimf
       This is METAFONT....
       **plain                 # you type plain
       (output)
       *input local            # you type this
       (output)
       *dump                   # you type this
       Beginning to dump on file plain....
       (output)
       %
    This should create a base file named plain.base (or something close)
    and should be moved to the directory which contains the base files on
    your system.
 
    Now you need to make sure METAFONT loads this base when it starts
    up. If METAFONT loads the plain base by default on your system, then
    you're ready to go. Under Unix, we might, for instance define a 
    command mf which executes ``virmf &plain,'' loading the plain base
    file.
 
    The usual way to create a font with plain METAFONT is to then start 
    it with the line
       \mode=<mode name>; mag=<magnification>; input <font file name>
    in response to the * prompt or on the METAFONT command line. If 
    <mode name> is unknown or omitted, then the mode defaults to proof 
    mode. If this has happened METAFONT will produce an output file
    called <font file name>.2602gf. The <magnification> is a floating 
    point number or magstep (magsteps are defined in _The METAFONTbook_ 
    and _The TeXbook_). If mag=<magnification> is omitted, then the 
    default is 1. For example, to generate cmr10 at 12pt for an epson 
    printer you would type
       mf \mode=epson; mag=1.2; input cmr10
    Note that under Unix the '\' and ';' characters must usually be 
    escaped, so this would typically look something like
       mf \\mode=epson\; mag=1.2\; input cmr10
 
    If you don't have inimf or need a special mode that isn't in the
    base, you can put its commands in a file (e.g., ln03.mf) and invoke
    it on the fly with the \smode command. For example, to create 
    ln03.300gf for an LN03 printer, using the file
	% This is ln03.mf as of 2/27/90
	% mode_def courtesy of John Sauter
	proofing:=0;
	fontmaking:=1;
	tracingtitles:=0;
	pixels_per_inch:=300;
	blacker:=0.65;
	fillin:=-0.1;
	o_correction:=.5;
    (note the absence of the mode_def and enddef commands), you would type
       mf \smode="ln03"; input cmr10