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