Familiarize yourself with the music hall ahead of time. Part of your job is to make the audience feel comfortable, so it's important that you seem comfortable yourself. Practice making your introduction from the performance area and have a friend or music hall employee listen to make sure your voice is clear and easy to understand. Experiment with the sound system at this time and make any changes necessary to ensure that you'll be heard.
Get to know the band. Listen to its music. Read old interviews. If possible, conduct an interview yourself. An introduction that communicates something witty and truthful about both the musicians and their music will pique the audience's interest in the show.
Appeal to the audience, but still be yourself. Knowing what kind of audience to expect will help you create an appropriate introduction that answers any questions audience members have and avoids seeming offensive or inappropriate. However, trying too hard to cater your introduction to what you think the audience will like is a bad idea. This is especially true with humor. If incorporating humor into your introduction, the best jokes are the ones grounded in reality that feel authentic and not obviously staged.