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