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