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