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