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