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