Best cue option for a live show? (not dj)

[Imanou]

Hello! I did my research but still can't find a solution, maybe i miss something obvious.
I'm preparing my live show, its me playing some hardware synts, vocoder, and some live looping and vst as well and a drummer who play samples, create drum loops and play on acoustic kit.
So what i need is making a cue for him and for me.
I use presonus 44sl interface which has only one headphone output. But it has extra line outs and i try to use them but the problem is that signal is in mono and what is worse only going in one ear in the headphones, so the question is - what is the simplest way for me and a drummer to organize monitoring with headphones?

[bosonHavoc]

do you need a separate mix for each headphone?
if not just get a headphone splitter and split the signal out the headphone jack..

but your stuck with the same volume
next option is a headphone mixer
which is basically the same thing but you get separate volume knobs

another thing you can do is each get your own small mixer like
then you can run a separate feed from the audio interface to each mixer..
you will need to run stereo channels for headphones which means two channels
the headphone jack has two channels which is why their are two rings on a headphone cable

so you could just get one mixer for the drummer and you could use the headphone out
run 2 channels (or more) to the mixer

what i find handy is have the music on one stereo channel then run the click mono on its own channel into a mixer
so that you can adjust the volume of the click individually