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)(11,19)(12,18)(13,15)(14,17)(16,20)(21,24)(22,23)(25,26,29,28)(27,33,35,31)(30,37,38,32)(34,39,40,36)(1,3,4,8)(2,5,6,7)(10,15)(16,23)(17,18)(19,24)(25,27,29,35)(26,31,28,33)(30,39,38,36)(32,40,37,34)(9,11,14,20,13,21,12,22)(10,16,18,19,15,23,17,24)(25,28,29,26)(27,34)(30,37,38,32)(31,39)(33,36)(35,40)(2,6)(5,7)(9,12,13,14)(10,17,15,18)(11,20,21,22)(16,19,23,24)(26,28)(31,33)(32,37)(34,40)A 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.