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