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