To transfer balances from exchange account to margin account do this step :
1. Click On Balances > Transfer Balances.
2. On the interface, set how much you want to transfer on the “Transfer” field, then select which currency (BTC, ETH, FCT, XMR etc.)
3. Set the “From” field as exchange, and “account to” as Margin, then click transfer. If successful you will see confirmation.
4.You can see now your balance will be moved from Exchange to Margin.
5. You can start doing margin trading after you have balance on your margin account.