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