This is what I copied, the first line is yellow
Private Sub Worksheet_SelectionChange(ByVal Target As Range)
Sub ColorSupplier()
Dim supplier As Range, ws As Worksheet
For Each supplier In Sheets("Summary").Range("A4", Sheets("Summary").Range("A" & Rows.Count).End(xlUp))
For Each ws In ActiveWorkbook.Sheets
If UCase(ws.Name) = UCase(supplier) Then
supplier.Interior.Color = ws.Tab.Color
Exit For
End If
Next ws
Next supplier
End Sub