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