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