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