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