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