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