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