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