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