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