It’s generally better to put effect like compressors and boosts on the effects loop or after the unit. The effects loop is after the gain so you can set your gain to a good level and then put other pedals in or take them out and it shouldn’t affect your gain.
As for the gain the general advice people give is to set so that the overload LED lights up on your loudest playing. Once you get past this point it will start to distort (not necessarily a bad thing). You shouldn’t need to boost it as it has heaps of gain available.
If you want a more pronounced effect move the peak nob clockwise.

I generally have mine in band pass mode, fast response, lo range peak between about 1 and 5 o’clock.

I Hope this helps.

Are you running other effects with it?

I have a Q-tron+ and if I put certain pedals in front (especially distortion) it can make the signal comming out of the Q-tron+ hotter. I just changed the order of my pedals and the problem was solved. I’ve noticed that other envelope followers do the same thing.