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