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