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