BLUE TONGUE SKINKS

So I am pretty sure I got the shed all off his feet and stuff when he was having a bath and I went over with a wet toothbrush very gently but how can I be defiantly sure I got it all off his feet. By the way he is not rubbing against stuff or anything so I am sure it's all off.

best way to tell is give it a good look over,especially the toes,if u helped with the toes should be all good