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