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