Let me risk saying something wrong or weird, otherwise I may be right...
I generally rinse mine in running water, you can gently use a bit of neutral soap and gently spread with your fingers.
You want your pad not only clean, but free of 'hard contaminants', so you should inspect it and remove carefully anything odd attached to it.
In the end, you may rinse it again with a quick detailer spray (any you would use as clay lube like ONR, UWW+, Meguiar's #34, mother's QD, any!), spraying it 4 to 5 times towards 'rinsing it', shake it and rest with the scrub face facing upwards.
Again, sorry if I'm wrong,
Kind Regards.