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