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