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