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