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