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