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