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