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