One vertex per element, one color per generator, with an edge from x to x·s.
(2,4)(9,10,15,20,16,21,14,30)(11,22,13,17,24,19,29,32)(12,18,27,34,28,35,26,39)(23,36,25,31,37,33,38,40)(5,6)(7,8)(9,11)(10,17)(12,23)(13,15)(14,29)(16,24)(18,31)(19,20)(21,32)(22,30)(25,27)(26,38)(28,37)(33,34)(35,40)(36,39) involution — undirected(1,2,3,4)(6,8)(9,12,15,27,16,28,14,26)(10,18,20,34,21,35,30,39)(11,23,13,25,24,37,29,38)(17,31,19,33,32,40,22,36)(9,13)(10,19)(11,14)(12,25)(15,24)(16,29)(17,30)(18,33)(20,32)(21,22)(23,26)(27,37)(28,38)(31,39)(34,40)(35,36) 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.