How do I change my cash account with IB to a margin account?

Step 1: Go to IB's web portal. Log in with your IB username and password.

Step 2: Click the profile icon on top right, then click 'Settings'

Step 3: Look for 'Account Type' selection under Account Configuration and click on it

Step4: Change "Account Type" to "Margin". Click "Continue" and complete the remaining steps.

DISCLAIMER: The following screenshots are taken from Interactive Brokers website, provided only as a setup guidelines, and may be changed from time to time subject to Interactive Brokers discretion. Piranha Profits Pte Ltd is not responsible for any loss or damages caused by inaccuracy and misrepresentation of the information.