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