Just about to order a reverb,and going to go with the upside down method with the remote to avoid damage when turning bike to mend punctures etc,on my bike there’s a place down the left for routing the cable on the frame so do I buy left and put upside down on right hand side of bars or do I buy right and put the remote on the left? How do you run yours

1×10 with remote upside down on left.

After fitting dozens of them to 5s, i’d say a much neater/smoother routing would be to the right side of the bar (check the upside down idea will work with your shifter/brake combo though, some make fitting in a comfy and useful position awkward).
Edit- the loop of hose required to allow the bars to spin without damaging it may cause rub on the fork crown if mounted on the left.

I just run mine on the left on the top of the bar with the cable running down the left..

I thought you only put your bike upside down when we were kids ???

I buy left and put upside down on right hand side of bars or do I buy right and put the remote on the left?

Which side would you prefer to have it on? Worth baring in mind that you may have to compromise shifter position a bit to squeeze it in, so moving the front shifter (if you have one) is usually preferable to moving the rear one

I’ve snapped 2 reverb levers run upside down. One was on my short HT (small cockpit) & one on my orange 5. Both times caught lever on baggy shorts when riding rather energetically. Levers now live on top.