how to avoid multiple instance for form

hello all,

I have form1 , Form2, form3. in form1 i have two button each when clicked displays Button2->Form2 and Button3->Form3. on button click i have the following code

 Private Sub Click2()
      
        Static Dim f3 As New Form3()
        f3.Show()
    End Sub

want to hide form2 while clicking button3. and the i must avoid multiple instance, only one object must be created.How could i acheive this. Please guide me