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