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