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