1993 Toyota Camry self tuning the 93 Toyota Camry

A basic tune would include a change of air filter, spark plugs, and maybe ignition wires. A major tune up would also include a PCV valve, distributor cap and rotor, and perhaps replacement of belts and fluids if needed.
With 90K I would also do a timing belt and water pump, and check all suspension parts such as motor mounts, struts, stabilizer links and bushings as they wear out and dry out.