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)(11,16)(12,20)(13,17)(14,19)(15,21)(18,22)(23,24)(25,26,30,31)(27,28,33,32)(29,34,38,39)(35,36,40,37)(2,4)(6,7)(9,11)(10,14)(12,18)(13,19)(15,22)(16,17)(20,23)(21,24)(26,31)(27,33)(34,39)(35,40) involution — undirected(1,3)(2,6)(4,7)(5,8)(25,26)(27,32)(28,33)(29,34)(30,31)(35,37)(36,40)(38,39) involution — undirected(1,4,5,2)(3,7,8,6)(9,12,13,21)(10,15,17,20)(11,18,19,24)(14,22,16,23)(25,27,30,33)(26,32,31,28)(29,35,38,40)(34,37,39,36)(9,11)(10,16)(12,18)(13,19)(14,17)(15,23)(20,22)(21,24)(25,28,30,32)(26,33,31,27)(29,37,38,36)(34,35,39,40)(9,10)(11,14)(12,15)(13,17)(16,19)(18,22)(20,21)(23,24)(25,29,30,38)(26,34,31,39)(27,35,33,40)(28,36,32,37)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.