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