How to improve the efficiency of the gas turbine cycles?

improve the thermal efficiency by increasing "turbine inlet temperature" more high temperature resistant material at turbine inlet vanes / combustion chamber lining.
increasing the pressure ratio for the compressor air.
cooling the inlet air.
cooling the after turbine exhaust and increasing the temperature difference, thus increasing the velocity of the gas flow across the turbine.

- make the inlet air cooler

- use gas oil instead of LDO

- make good maintenance

- check air filter for clean

You can use combined cycle (gas + steam )to improve efficiency

nikhil.......excellent answer.........no comment.