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