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