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