One way: Pass the form to the class.

In the form:
[VBA]Dim cFoo as clsFoo
Set cFoo = New clsFoo
Set clsFoo.Form = Me[/VBA]
In the Class:
[VBA]Private moForm As Object
Public Property Get Form() As Object
Set Form = moForm
End Property
Public Property Set Form(oForm As Object)
Set moForm = oForm
End Property
Private Sub classCmdButtons_Click()
Form.Hide
End Sub
[/VBA]