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