The below steps will walk you through obtaining your API Login ID and Transaction Key from account.authorize.net to with SMC commerce settings.

Note: You must have already signed up for an Authorize.Net Merchant account in order to log into your account.

1. Start by logging into your account at  account.authorize.net

2. On the next screen click "Account" from the top navigation.

3. Click "API Login ID and transaction key"

4. Copy or note your API Login ID

5. Enter the answer to your secret question

6. Copy or note the Transaction Key.  It's important to record this now as it's not displayed again