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