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