The theory is simple.
Consider a surplus on the external balance - where we are today.
Floating Exchange Rate Regime. There is an excess of demand for ringgit (from exports) over that of foreign currencies (for imports). The ringgit strengthens against foreign currencies. There is no change in the holdings of the foreign reserves of the central bank because the central bank is not involved in the forex market. It is truly free.
Fixed Exchange Rate Regime. The central bank does not want the exchange rate to change. The central bank issues more ringgit to buy the excess foreign currencies from the external surplus. The ringgit rate does not change. Foreign reserve holdings of the central bank increases. The quantity of ringgit in the economy increases.
Conclusion. To engineer a strengthening of the ringgit, just let the ringgit float (when there is an external surplus). It's a bit harder in a deficit situation, admittedly.