Soaking is a great way to help with shedding or hydration. But it's not always necessary. Unlike geckos, uros take their sweet time in shedding. I would just let it take it's own course (provided your uro has stuff he can rub himself against to help tear the pieces). The soak would only be necessary if you notice particularly stubborn pieces (pay special attention to the toes and tail, they have the most problems).
hope that helps 
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1.3 Uromastyx Maliensis (Ricky, Quinn, Anna, Drusilla)
0.2 Varanus Timorensis (Zealot, Willow)
1.1 Varanus Acanthurus (Eddie, Roxie)
0.0.2 Uromastyx Aegypticus (Kronk, Yzma)
0.0.2 Ceratophrys Ornata (Mojo, Jabba)
0.1 Geochelone Carbonaria (Turtle)
1.0 Rhacodactylus Ciliatus (Smeagol)
Emily
www.egomantra.com/npoh