As a Songwriter or Artist only you really know when your song is written and you've said everything you need    to say. Here is a list of things to check off before you send your song out to a producer for production. 

1. This one may seem obvious but your song needs to be finished. Don't send a producer that you don't already have a working relationship with an unfinished song.

2. Make sure your song has a workable structure that makes sense. Avoid odd measure bars unless you are including them with purpose. Compare your song to Commercial Releases that are similar to your song. If you're not sure about timing try to work with a guitarist, keyboard player or drummer that can help with timing and arrangement. 

3. Make sure your chord progression works with your melody. If you're not certain about this, work with a guitar or keyboard player to iron out any potential problems in this area. 

4. If you will be recording the vocals yourself make sure you have decided on a key and tempo. Make sure you can hit all of the notes in your melody comfortably without having to reach too much. Also be sure the tempo is right so that you can comfortably fit all of the words without having to rush. Alternatively you don't want the song to drag either. If you are not certain about this let your producer know up front and work it through together with your producer. 

5. Make a good Worktape. A worktape is simply a recording of your song. It should represent the basic structure and melody of your song. Your worktape needs to be of decent quality so that all of the audio can be heard and understood clearly. You'll need a guitar or keyboard accompaniment so that the arrangement can be heard. It's important to make your best impression up front and give your producer the highest quality worktape that you can make. 

6. Follow these simple guidelines and you'll be ready to take the next step - Recording your song!