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