La boucle For Each

Dim element As TypeDeLElement
For Each element In collection
    ' instructions sur element
Next element

Sub SignalerNegatifs()
    Dim c As Range
    For Each c In Range("C2:C500")
        If IsNumeric(c.Value) And c.Value < 0 Then
            c.Font.Color = RGB(200, 55, 45)
        End If
    Next c
End Sub

Sub ListerFeuilles()
    Dim ws As Worksheet, ligne As Long
    ligne = 1
    For Each ws In ThisWorkbook.Worksheets
        Worksheets("Sommaire").Cells(ligne, 1).Value = ws.Name
        ligne = ligne + 1
    Next ws
End Sub

Sub Majuscules()
    Dim c As Range
    For Each c In Selection
        If Not c.HasFormula Then c.Value = UCase(c.Value)
    Next c
End Sub