This article will show you how to change the perpetual contract you want to trade before submitting an order.
How to Select an Instrument
By default the trading chart shows the BTC-PERP contract. To switch to trading the ETH-PERP contract, then go to the instruments panel and select 'ETH Perpetual':
You can also change the trading instrument by using the browser panel. Navigate to the panel on the left hand side and click on ETH-PERP, as shown below:
You can then submit an order or enter a position for ETH-PERP, then go to the instruments panel to change back to BTC-PERP.
The currently selected trading instrument will be displayed by the instrument panel (which is found above the price chart) and the browser panel (found directly below the order panel). Both are highlighted in the image below: