Summarize this article:

Some shells might shoot into the air with a zig-zag, while others will shoot additional stars after a delay. Carefully read the label on each shell so you’ll know exactly how it should behave. No matter how excited you are about the show, safety should be your first concern. Wind can cause sparks from fireworks to behave erratically, potentially causing fires to nearby structures or injury to your audience. If the forecast calls for winds higher than 11-16 knots, or 12–18 miles per hour (19–29 km/h), you may want to take larger shells out of the show or reschedule it altogether. You don't have to cancel your show because of light rain as long as you protected your fuses with plastic bags, but you might want to delay the show for the comfort of the crowd. Anyone who will be near the launch area should wear protective gear to protect their eyes and ears. You might also want to wear fire-retardant clothing.  Have a few friends plan to stay close during the show in case you need help dousing out flames. If you do catch on fire, drop to the ground and roll to smother the flames. Stray sparks might ignite any extra charges or fuses you have on hand. Keep them at least 10 feet (3.0 m) from your mortar trough. Never keep charges or fuses in your pocket, as they could ignite and cause you serious injury. Instead, wait for about 30 minutes, then douse them in water.

Summary:
Read the instructions on each shell so you know what it will do. Pay attention to the weather the day of the launch. Wear safety glasses and ear plugs during the launch. Keep spare charges or extra fuse 10 feet (3.0 m) away from the launch area. Do not attempt to relight fireworks that don't go off.