All of the integrated environments of the Intel Edison will copy your executable from your development PC to the Intel Edison. If you want to develop outside of these environments, however, you will have to copy the code over yourself. Here are several solutions that don't involve creating a custom flash image.
This gist assumes that you are able to, at minimum, access the Edison console through USB. Some methods require additional connectivity. There are two basic approaches. Network methods are for when you have access to Edison over wifi, and the sneaker net methods are for when you don't.
If you have wifi configured, there are other ways of getting your files onto the Edison. None of these methods require the installation of any other software onto the Edison. If you can SSH into the Edison over wifi, then these methods will work.