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