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