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