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