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