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