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