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