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