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