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