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