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