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