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