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)(11,17)(12,15)(13,16)(14,19)(18,23)(20,22)(21,24)(25,26,31,30)(27,32,36,39)(28,29,33,37)(34,35,38,40)(9,11,13,19)(10,14,16,17)(12,18,20,24)(15,21,22,23)(25,27)(26,32)(28,35)(29,38)(30,39)(31,36)(33,40)(34,37)(1,3,5,4)(2,6,7,8)(9,12,13,20)(10,15,16,22)(11,18,19,24)(14,21,17,23)(25,28,30,37,31,33,26,29)(27,34,32,35,36,38,39,40)(10,16)(14,17)(15,22)(21,23)(28,33)(29,37)(34,38)(35,40) involution — undirected(1,4,5,3)(2,6,7,8)(11,19)(14,17)(18,24)(21,23)(25,29,26,33,31,37,30,28)(27,35,39,34,36,40,32,38)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.