Four steps for margin trading:
Step 1: Enable margin account
Choose [Trade] →[Basic] at the navigation panel, select [Margin] tab at any margin trading pair, then click [Open margin account].
Enable the margin account by clicking [I understand] after reading the Margin Account Agreement.
For complete details, visit How to Enable a Margin Account on Binance.
Step 2: Transfer in
Select [Transfer] to transfer from spot wallet to margin wallet.
Select the coin you want to transfer, enter the amount and click [Confirm transfer] to transfer.
For complete details, visit How to Transfer Funds to Binance Margin Account.
Step 3: Borrow/ Trade
Select [Borrow] to perform Margin Buy or Margin Sell.
For complete details, visit How to Borrow Funds on Binance.
Step 4: Repay/ Trade
Select [Repay] to perform Margin Buy or Margin Sell.
For complete details, visit How to Repay Debts on Binance.