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