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