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