By default, Forex Copier copies orders with the same lot size but you can set to multiply the lot size of copied order by selected value.
Example 1: Source account trades on $1000 account, your account is $50000, if you copy the orders from Source account as is you will get too small profit (loss).
   So you can set multiplier 50, and when the order on Source account is opened with 0.1 lot you will get an order with lot = 5. 
Example 2: Source account  trades on account $100000, your account is $20000. It will be dangerous to your account to open the same lot, sometimes it will be impossible.
   So you can set multiplier 0.2 and when order on Source account is opened with lot = 10 you will get an order with lot = 2.
   If resulting lot is smaller than minimum lot in your MetaTrader then this order will be opened with minimal lot. 
 
You can find Lot Multiplier option in Forex Copier 2 application, just click “Settings” button on Receiver account, go to “Lot/risk management” tab and activate “Use custom lot size”.
Then enable “Multiply lot size from Source account by:” and set necessary value there.
After this, please click “Save and Finish” and “Apply New Scheme” buttons to apply these new settings.