One vertex per element, one color per generator, with an edge from x to x·s.
(2,4)(6,7)(8,12)(13,14)(15,20)(16,18)(17,19)(22,26)(23,29)(24,32)(34,36) involution — undirected(5,6,9,7)(8,11,12,10)(13,15)(14,19)(16,20)(17,18)(22,26)(24,32)(27,30)(31,35)(5,6,9,7)(8,10,12,11)(13,14,18,16)(15,20,17,19)(21,22)(23,30)(24,28)(25,26)(27,29)(31,36)(32,33)(34,35)(1,2)(3,4)(5,7,9,6)(8,10,12,11)(13,16,18,14)(15,20,17,19)(21,23,25,29)(22,27,26,30)(24,31,32,35)(28,34,33,36)(5,8,9,12)(6,10,7,11)(13,17,18,15)(14,19,16,20)(21,24,25,32)(22,28,26,33)(23,31,29,35)(27,34,30,36)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.