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