He studied with Yuriy Oliynyk, Jerry Murphy, Frank Wasko, David Baker, James Tocco, Karen Shaw, Bill Dobbins, and Rayburn Wright.
[1] In 1992 he began directing the music theory and jazz studies programs at American River College,[2] and released the album Treasure Chest, with Joe Henderson, Jeff "Tain" Watts, and Robert Hurst.
In 1998 and 2000, Gilman toured twelve countries on the African continent as a part of the Kennedy Center/USIA Jazz Ambassador program.
Although originally influenced by ragtime music, Gilman in his teens discovered jazz pianist Dave Brubeck.
Later he listened to the recordings of Oscar Peterson, Herbie Hancock, Chick Corea, McCoy Tyner, John Coltrane, and Miles Davis.