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