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