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