What is the maximum leverage? How can I change it?

The max leverage for an account is 1000:1 using the *Smart Account. 

You can submit a leverage change request on the Customer Portal.

1. Expand the Accounts tab in Trader's Menu.
2. Click Accounts Overview.
3. Click the relevant account number highlighted in blue.

NOTE:

*Account's leverage changes according to the account balance.  Please refer to the page below for the trading conditions of each account type.
https://miltonmarkets.com/account-types