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