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