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)(11,18)(12,20)(13,15)(14,17)(16,22)(19,23)(21,24)(25,26)(27,34)(28,36)(29,31)(30,33)(32,37)(35,39)(38,40)(3,7)(5,8)(9,11,14,13)(10,15,17,18)(12,21,22,19)(16,24,20,23)(25,26)(27,34)(28,32)(29,31)(30,33)(35,40)(36,37)(38,39)(1,2)(3,5)(4,6)(7,8)(25,27,30,29)(26,31,33,34)(28,35,37,38)(32,39,36,40)(1,3)(2,5)(4,7)(6,8)(9,12,14,22)(10,16,17,20)(11,19,13,21)(15,23,18,24)(25,26)(27,31)(28,32)(29,34)(30,33)(35,39)(36,37)(38,40)(1,2)(3,5)(4,6)(7,8)(9,10)(11,15)(12,16)(13,18)(14,17)(19,23)(20,22)(21,24)(25,28)(26,32)(27,35)(29,38)(30,37)(31,39)(33,36)(34,40) involution — undirected(9,13,14,11)(10,15,17,18)(12,19,22,21)(16,24,20,23)(25,29,30,27)(26,31,33,34)(28,35,37,38)(32,40,36,39)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.