Are you trained and experienced in making a Flash file? Have you made one which can possibly be put up for grabs?
If you are interested to know how you can make a single Flash item, then you should educate yourself first about the topic. For instance, you would not immediately know how you can make fun Flash animation if you are not technology oriented or if you have not received an opportunity to learn more about the techniques being used by other Flash makers. Being too technical, you might really need to go to school or attend a serious seminar on how to make a Flash item work. The animation is already a famous theme for a Flash but it could take time and skills to make one.
Now, if you are ready to make your Flash components without any possible mistakes, you should also be ready to sell them online so that you will earn more from this skill of yours. Even if you may have worked on another field far from technology and Flash making, this should not mean that you cannot explore this field of work too. You can insert this kind of work into your regular schedule whenever it gets a little vacated.
If you are ready to sell, make sure that you will negotiate with a website that will allow you to claim your payment in very simple ways. You should also look for those websites which has low minimum requirements when it comes to claiming your payment so that you will have money to turn to immediately when you need it.