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