Prayer is the way you communicate to God. Some people claim that God does not answer prayer, but this is not correct. God answers every single prayer, just not always in the way the person wanted the prayer answered. The answer can be “yes”, but often it is “no” or “not now”.
How does He choose which answer? God only knows. Literally. If your prayer is in tune with his wishes, and it would be good for Him and/or good for you without being harmful to Him, then the odds of “yes” can be fairly good. Otherwise, the chances of “yes” would be pretty slim.
Prayer can be efficient in times of need; “Help!” might be a very good prayer as your car crashes through the guardrail hundreds of feet in the air. However, usually you will want to approach your communication with a fair degree of formality, particularly if you are asking for something.
First of all, “address” your prayer. Who are you talking to? Use the name or title or relationship you most admire, or which the entity you are talking to is claimed to prefer. “Hey, you” probably would usually not be one of the better choices.
Next, don’t just list your wants. This is COMMUNICATION, not a spiritual Home Shopping Network. Comment on the good stuff you have experienced. If you are asking for something, be polite about it and try to keep it aligned with the views which it is claimed the one you are praying to holds.
And if you get a “no” or “not now” answer, don’t freak out. Expect it, so the “yes” answers are special.
Again, you are conversing, as part of a relationship. How often? As often as your relationship expects, plus any time you just need to chat. How long? As long as it takes and no longer.