Visual Basic.NET - como pasar de un formulario a otro

Public Class Form1

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

        Dim f2 As New Form2

        f2.Show()

        Me.Hide()

    End Sub

End Class

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

        Public Class Form1

        Dim f2 As New pantalla_de_polizas

        f2.Show()

        Me.Hide()

    End Sub

End Class

Dim cambiar As New Form2

cambiar.Show()

Me.Hide()

Private Sub CmdAceptar_Click()

If Val(Text2.Text) = lunes Then

FrmLunes.Show

Unload Me

End IF

End Sub

MDI.form2.PerformClick()

My.Forms.form2.Show()

Private Sub mnu_form2_Click(sender As Object, e As EventArgs) Handles mnu_form2.Click

     '// Si está abierto, lo activa, no lo vuelve a abrir 2 veces

     Dim sForm As String = ""

     For Each f As Form In My.Application.OpenForms

        If f.Name = "form2" Then

            sForm = f.Name

            My.Application.OpenForms("form2").Activate()

            Return

        End If

    Next

    '// Si está cerrado, lo abre de la siguiente forma:

    Try

        My.Forms.form2.MdiParent = Me

        My.Forms.form2.Show()

    Catch ex As Exception

        MessageBox.Show("Error N° " & Err.Number & Environment.NewLine & ex.Message,  "Aviso", MessageBoxButtons.OK,

                                         MessageBoxIcon.Error)

    End Try

End Sub