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