Did we mention what a bad idea it is to use real flames for any kind of show or display? It isn't that you can't safety burn a candle in a jack-o-lantern, it is all the unexpected, improbable things that go can wrong. The thing is that when something goes wrong with fire, it tends to go really, really wrong...possibly fatally wrong. Don't use real flames if you don't have to. And if you do have to, build in every possible safeguard.
The following suggestions are just some guidelines, they are not exhaustive, and they don't even take into consideration local fire safety laws where you live. Compliance with the law as well as good common sense are critical in the safe use of flames.
First off, whenever using live flame, put it inside a container that can safely contain the flame. The fireplace in your home can safely contain a fire because it is non-flammable, heat-resistant, is stable and not going to spill over and finally has safeguards to keep things out and away from the flames. These principles should be applied to any flame effect. The container should be fire proof and heat-resistant. The container should be stable. If a tiki torch gets jostled and knocked into the grass tiki-hut around your backyard bar - game over. Fire should be situated so that it cannot fall, be blown, moved or otherwise knocked over. Furthermore, it should be far enough away from flammable objects that nothing can fly into the flame. Outdoor curtains, tree branches, people's clothing nor any manner of flammable thing should be able to reach the flames.
Another good precaution, generally speaking, is to keep the flame source higher than things surrounding it. A firepit might be really cool, but people walking by might catch a skirt or beach towel on fire. It is best if flames are out of reach. When this isn't practical, then other safeguards must be used to ensure that accidental contact with the flames cannot occur.
Whenever using flames for effect, ambience or warmth, always keep one or more fire extinguishers nearby and visible.