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