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