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