How do I orient a fireworks cake?
The first and most important thing when setting up a cake is to pay attention to the orientation. So assuming you have a cake with angled tubes, you want to make sure you have the cake oriented in such a manner that the "fan" will be seen by the audience. You want the audience to enjoy the cake as it was meant to be seen, and not the side perspective. See illustration below:
What else needs to be done to setup a fireworks cake?
You must then "foil" the cake. We foil the cake for the same reason we foil the finale mortars. Covering the top of the cake with foil keeps any sparks produced by other devices in the show, particularly nearby cakes, from igniting the cake prematurely. If you wrap the cake entirely with foil and not just the top, you are also preventing the cake from being aerated after it shoots. The cardboard material the cake is made from will be smoldering afterwards and even a slight breeze will cause it to catch fire. Is this a hazard? No. But it doesn't look good if the customer can see fires during the show. There are some instances where you don't want this to happen anyway, such as rooftop shows. In addition to these, if it is an electrically fired display where the cake would have an "address", you want to write this address on the top of the foil to make it easier to debug if a continuity issue comes up. Watch a video explanation of a fireworks cake setup.
Is there any special considerations for the larger cakes?
Yes. The larger cakes, need to be placed in the wooden "cake boxes" in case of a malfunction. Remember that a cake fires one after another from start to finish with no way to stop it. So if a tube explodes, the other surrounding tubes could be knocked out of place pointing in an undesirable direction (towards you or the audience). So, to prevent this, we place these large cakes in the wooden boxes to keep all tubes pointed strait up even in the event of a malfunction. "Large" cakes being defined as 2.5" tube diameter or larger. Watch the fireworks cake box video.