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