Look for the guide with a blue badge, a blue bag or a black backpack. Meet by the center statue. It's a big square with 2 fountains on each side and in the center a high column with a man on the top. If you are in a square with a statue of a man on a horse, you are in the wrong square.
We only pick up at a Hotel if it's a short walk from the original meeting point. If your Hotel is not shown on the list, it's because it's outside that limit, therefore the meeting point has to be Praça Dom Pedro IV (Rossio)