A person performs an act of worship until it becomes a habit (e.g. cooking for family for sake of Allah), does a person need to renew intention for that worship each time to receive the reward? or can they intend to do that act of worship recurrently but make the intention once at the beginning.
We need to have a continuous intention in our heart that every good act we do (even cooking and cleaning the house) is an obedience to Allah. So we wake up and automatically we will think how to please Allah today. By taking care of my husband, by being good to my neighbours etc.
At the beginning we will need to concentrate in initiating an intention. Then, by time, we will find ourselves doing all acts while putting in our minds and hearts that they are for the sake of Allah. The intention will be there.