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