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