When starting out it can be expensive and premature to invest in props, so it makes sense to cheaply build your own props. We have put together some basic instructions on how to build a range of props both in the practice and fire variants. And there is no reason you can't build props that match the quality of a lot of props that you buy on-line, often it is patience and attention to detail that will take your prop to the next level. And don't forget to experiment and make some crazy new flow props!
Don't forget to check out the Materials and Techniques as well, they can help you build better props and create new props.