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