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