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