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