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