Press 'm' (``set multiplot'') from the main menu to set up a multiplot. Note that a ``multiplot'' (multiple columns plotted from the same file) is different to plotting ``multiple plots per page'' (divide the plotting page up into panels). The number of panels across and down on a page can be changed (see ??) irrespective of whether or not you are also plotting multiple columns from the same file.
Once you have gone through the options to set up a multiplot, to actually plot what you have set simply type the number of the column corresponding to ``multiplot'' at the $y-$axis prompt.
To make a plot using different particle types in each panel (e.g. gas density in one panel, dust or dark matter density in another), use 'm' (``set multiplot'') from the main menu. If multiple types are present in the data read, the option appears to specify the particular types you want to use for each plot.
For example, after pressing `m' at the main menu we eventually arrive at the question:
use all active particle types? (default=yes): n
Answering ``no'' brings up a possible list of types:
1: use gas particles 2: use ghost particles 3: use sink particles 4: use star particles 5: use unknown/dead particles Enter type or list of types to use ([1:5], default=1): 1,3
Thus entering e.g. ``1,3'' specifies that only gas and sink particles should be used for this plot.
Note that this is more specific than simply turning particle types on and off for all plots, which can be achieved via the ``turn on/off particles by type'' option in the o) menu (see §??).