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