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