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