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