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