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