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