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)(27,33)(28,37)(29,31)(30,36)(32,39)(34,40)(35,38)(9,11)(10,14)(12,19)(13,18)(15,23)(16,22)(17,20)(21,24)(25,27)(26,30)(28,38)(29,34)(31,35)(32,40)(33,37)(36,39) involution — undirected(2,5)(6,8)(9,12,13,20)(10,15,16,24)(11,17,18,19)(14,21,22,23)(27,34)(30,35)(33,40)(36,38)(11,18)(14,22)(17,19)(21,23)(25,26)(27,35)(28,32)(29,31)(30,34)(33,38)(36,40)(37,39) involution — undirected(1,3,4,7)(2,6,5,8)(10,16)(14,22)(15,24)(21,23)(26,31)(30,35)(32,37)(33,40)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.