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