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