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