Just wait till you find that you've enough profit then convert it into your currency then buy again when price get low again rinse and repeat.
That will be a too long process. Rather than that start trading with a small amount. When you turn it into fiat there will be a fee, although now fees are there even on transactions. But that will be a more profitable thing to grow your BTC.
Yeah making profits from buying and selling bitcoins will take a long time to grow your coins better option would be to put that money in altcoin trading and start making small profits and eventually it will help you in growing your coins in long term.
yes trading alt coin is also a good way of making money but in fact currently the price of bitcoin expected to increase therefore if a person simply hold bitcoin in present time he can surely make more profit that what he can make from trading alt coin. more ever holding bitcoin is also a safe way of making money.