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