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