Join a stereo track to a mono

What is the best way to join a stereo track to a mono in reaper? Thank you in advance

I need to make a track to play on live shows. So i'v to take my stereo track and transform it in a mono track (joining the 2 channels in one mono channel). After that I will put the click track on left channel and my new mono track on right channel. thank you

Keep the mono track and the click on separate tracks for now; hard-pan them left and right; render them into a stereo file. If this all seems a bit confusing, we may need to backtrack and cover some basics for you -the newbie section might help here too. Let us know what you get and don't get and we'll see what we can do to help... >

I know how to pan and render the click track and the mono track in a stereo file. But actually I don't have a mono track but a stereo. what I'm asking is: how to join the two channels of a stereo track in a mono track. thank you

put a dummy plugin on the track (bypass it) rightclick waveform--aply track fx to item as new take(mono output) then crop to active take (alt+shift+t)

or in the action list "track: render tracks to mono stem tracks(and mute originals)"

I won't tell you people that you can change the channel mode in the item properties. No, i won't tell you that...