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