Numbers 3 and 4 are outdated and should not be used anymore. Especially the word "Fräulein" is nowadays considered "politically incorrect", because it's usually none of your business whether a woman is married or not.
What I usually to to get the attention of a waiter or waitress:
1. Without any words, just try to make eye contact. First by looking at them, and then maybe by waving your hand when they look in your direction. A good waiter or waitress should notice this and either come to your table or say something like: "Einem Moment noch" or "Komme gleich."
2. If this doesn't help, say "Entschuldigung!" On a second attempt you can expand it to something like: "Entschuldigung, könnte ich bitte..." - basically starting to say what you want from them.