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