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