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