Here we have posted an article about how to ask an Angel a favour. Now, we are going to see how to ask a favour from a God or Goddess. Before I go on, I must make clear that you cannot force a God / Goddess to do whatever you want. He/She is going to do his/her will. But a God would never do anything that you are not asking of him to do for this would be against your free will, and this is something that no divine spirit would do. That is the reason we need to ask for the favour in order to receive it.
Then choose the God you are going to ask for your wish to come true. You may choose your most beloved deity, or a God most appropriate for the kind of favour you are asking. Anything is going to work, but be careful of the nature of the God, as the path he is going to take to fulfil your wish may not be a desirable one.
This is your contract or agreement with the God. This is something that you are going to do only the first day. Then explain to the God why you want this wish to be fulfilled, and how the manifestation of the wish will bring you joy. If you want, you can ask for advice as well.