Workflow > Set a specific Custom Form for New Transaction Triggered via Make Copy

Below is a sample workflow to set a specific custom form for a new transaction triggered via make copy of an Estimate.

Steps:
1. Create a new workflow with the following summary settings (Customization > Scripting > Workflows > New)
 a. Name = Default Custom Form - Make a Copy
 b. Record Type = Transaction
 c. Sub Types = Estimate
 d. Event Based = On Create: Checked
 e. Trigger Type = Before Record Load
 f. Event Type = Copy

2. Click State 1 and add a  Set Field Value action

3. Below are the settings used for the Set Field Value
 a. Trigger On = Before User Edit
 b. Condition = "Custom Form != My_Custom_Estimate"
 c. Parameters> Field = Custom Form
 d. Value> Static Value> Selection = My_Custom_Estimate

Note: The criteria for the condition in the "Set Field Value" action was set to ensure that the form is not stuck on a loop since changing the custom form causes it to reload and trigger the "Before User Edit" again.