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