Here's an example whitout a Timer object.
Code:
    Dim t As Single
    Dim blnColor As Boolean
    Dim lngCounter As Long
    
    t = Timer
    Do While Timer < t + 4
        lngCounter = lngCounter + 1
        If lngCounter = 20000 Then
            lngCounter = 0
            blnColor = Not blnColor
            Label1.ForeColor = IIf(blnColor, vbRed, vbWhite)
        End If
        DoEvents
    Loop