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