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