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