Casto was born in Delaware, Ohio, in 1977. He received his B.A. from Earlham College in Richmond, Indiana, and his M.A. and M.F.A. degrees from the University of Iowa. After serving as an assistant professor at Mount Mercy and Kansas State universities, Casto returned to the UI, where he is an assistant professor of art teaching ceramics and a member of the Public Digital Arts Faculty Initiative. He was a 2011-2012 long-term artist in residence, and the 2011 MJD fellow at The Archie Bray Foundation for Ceramic Art in Helena, Montana, and has exhibited work internationally in Spain, Croatia, Italy, Austria, Slovenia, Belgium, China, and Japan.

Casto was awarded second place in the 2013 VII Bienalle International de Ceramic, in El Vendrell, Spain, and the 2010 FuLe Prize by the International Ceramic Magazine Editors Association in Fuping, China. He was selected as a recipient of a 2015 Emerging Artist award by the National Council on Education for the Ceramic Arts (NCECA), and completed a solo exhibition at Galleria Salvatore Lanteri in Milan, Italy, in 2016.