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