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