1. Go into Accounts Payable
2. Click on Banks
3. Click on Print checks and record bank drafts
4. Click on the Format tab
5. Under Payment Information you can change the payment format

Or

1. Go into Accounts Payable
2. Click on Banks
3. Click on Edit account details
4. Go to the Payments tab
5. Highlight the appropriate transaction type (ex. Accounts Payable Computer Check)
6. Set a default payment form at the bottom of the screen
7. Save and close

For additional information regarding the available check formats in Accounts payable click here.