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