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