Originally Posted by homebrewer_99
Ceramic Mug (without a pewter lip/top): Lay it over on its side for a refill.
Ceramic Mug (with a pewter lip/top): Closed means you're OK. Open means a refill. If you look like you don't know what you're doing and leave it open they will check and correct your "gasthaus etiquette".
Other than that they can read the "glasses" from across the room and don't bother you like American servers do.
The glasses have markings on the side (near the top) that indicate how much beer is supposed to be in the glass - it's a law. If you get one that is below the line you can send it back to be filled.
Oh, that's good. Those clever Germans. Some friends once tried laying our glasses on the side because the bartender was not very interested in us and way too interested in the hottie at the end of the bar. He noticed that the glasses were empty becasue they were on their side, but generally just got annoyed about it.
I can't tell you how many times I tried to get a bartender to fill my mug or pitcher all the way, instead of leaving it half head because they don't know how to pull a draft. A full 100% of the time, they've just looked at me like I just landed from Mars, instead of "Geez, I guess I did give you too much foam. I'll top it off for you right away, Sir!"