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