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