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