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)(25,26,31,30)(27,33,28,32)(29,34,37,38)(35,40,36,39)(1,2,5,8)(3,4,7,6)(10,15)(12,17)(16,21)(20,22)(25,27,31,28)(26,32,30,33)(29,35,37,36)(34,39,38,40)(1,3)(2,6)(4,8)(5,7)(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)(25,28,31,27)(26,33,30,32)(29,36,37,35)(34,40,38,39)(1,3)(2,4)(5,7)(6,8)(9,12)(10,11)(13,22)(14,17)(15,18)(16,24)(19,21)(20,23)(25,29)(26,34)(27,35)(28,36)(30,38)(31,37)(32,39)(33,40) involution — undirected(1,4)(2,7)(3,8)(5,6)(9,13,14,23)(10,16,15,21)(11,19,18,24)(12,20,17,22)(25,30,31,26)(27,33,28,32)(29,34,37,38)(35,39,36,40)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.