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