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