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