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