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