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