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