External FX Send and Return Gain

What method do you guys and gals use to set the send and return gain on external FX’s? I use the interface meter to see if it’s clipping, but I was wondering if anyone has a more better method!

Thanks,

I don’t use external FX, but you method sounds fine to me, if the metering on your interface is precise enough. Maybe your interface has also a mixer app like e.g. Totalmix for RME, that is where I check any inputs for level.
You could also just insert Supervision after the external FX.