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