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