One vertex per element, one color per generator, with an edge from x to x·s.
(2,4)(5,6,10,11)(7,9,8,12)(13,14)(15,19)(16,20)(17,18)(22,26)(23,29)(24,31)(34,36)(6,11)(9,12)(14,17)(15,20)(23,29)(27,32)(30,35)(34,36) involution — undirected(5,7,10,8)(6,9,11,12)(13,15,18,20)(14,19,17,16)(21,22,25,26)(23,27,29,32)(24,28,31,33)(30,34,35,36)(1,2)(3,4)(5,8,10,7)(6,12,11,9)(13,16)(14,15)(17,20)(18,19)(21,23,25,29)(22,27,26,32)(24,30,31,35)(28,34,33,36)(5,9,10,12)(6,7,11,8)(13,17,18,14)(15,16,20,19)(21,24)(22,28)(23,30)(25,31)(26,33)(27,34)(29,35)(32,36)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.