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