Suffit de pas mettre de border, tout simplement.
Si tu veux permettre le déplacement de ta forme sans border :
 
Public Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, _
                                                                       ByVal wParam As Long, lParam As Any) As Long
 
Public Const WM_NCLBUTTONDOWN = &HA1
Public Const HTCAPTION = 2
Public Declare Sub ReleaseCapture Lib "user32" ()
 
public sub MoveWindow()
 
  Call ReleaseCapture
  Call SendMessage(hWnd, WM_NCLBUTTONDOWN, HTCAPTION, 0&)
 
end Sub