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