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