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