One vertex per element, one color per generator, with an edge from x to x·s.
(1,2) involution — undirected(3,4)(5,6)(7,8)(9,17)(10,14)(11,23)(12,15)(13,19)(16,25)(18,31)(20,30)(21,28)(22,35)(24,27)(26,33)(29,34)(32,38)(36,37) involution — undirected(7,9,12,20)(8,13,15,27)(10,18,21,32)(11,24,25,19)(14,26,28,37)(16,30,23,17)(22,36,34,33)(29,38,35,31)(4,6)(7,10)(8,14)(9,18)(11,22)(12,21)(13,26)(15,28)(16,29)(17,31)(19,33)(20,32)(23,35)(24,36)(25,34)(27,37)(30,38) involution — undirected(10,21)(14,28)(18,32)(22,34)(26,37)(29,35)(31,38)(33,36) involution — undirected(8,15)(13,27)(14,28)(16,23)(17,30)(26,37)(29,35)(31,38) involution — undirectedA 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.