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