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