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