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