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