As you are thinking, and planning a special evangelistic event, there are some fundamental considerations. The two important aspects are prayer and promotion. To specifically pray for people who will be invited to the meetings and for just about every aspect of the event is a key to a successful outreach.
Much effort and some budget should be dedicated toward promotion. You will need a plan to collect information about people attending the event, especially from those who will make a decision to receive Christ as their savior. A follow-up course, or new believer's course should be used to help them understand salvation, and the foundation of their new-found faith.
The stage must be in such a position so that everybody can clearly see the performance. Illusion is a special art that often requires the audience to be directly in the front, and not on the sides, or behind the performer. Some programs can be planned for an audience that is all around, but this would need to be specifically communicated ahead of time.
What can we do if we want our halls and churches to be filled the night of the event? First we need to pray, and encourage as many as we can to do so. Then we need to promote the event, and encourage everybody to come and invite friends, relatives, neighbors and workmates.
Through advertisement we can also reach into the general public, those who have no direct contact with church members. It would be good to first see where you could get some free advertisement. A good flyer and poster are a must. You can download some of the following items to help you prepare your promotional, and follow-up material: