If you are talking about the second instance then you would use the name for the second instance rather than form2 also if talking about a second instance it needs to be defined with a scope that is accessible to the routine.
Form2.Caption="Whatever you want"
In other words if in your command click event you had
Then MyNewForm2 would not be a valid reference outside that sub routine
Dim MyNewForm2 as New Form2
You would need to dim it at the top under the declarations or in as public in a module to access it outside a routine.