Saint Theophan offers us some advice about prayer.
The essence of prayer is the raising of the heart and mind to God...You must train yourself in remembrance of God, and the means for doing this... is short prayer, in which you continually repeat the thought, "Lord have mercy!" "Lord, Jesus Christ, Son of God, have mercy on me a sinner!"In addition we need to train ourselves to focus on pray and not to let our minds wander. Saint Theophan address this as follows:
Make this your rule: always be with the Lord in mind and heart; never allow the thoughts to wander, but when they do, call them back again and force them to stay at home in the house of the heart and speak with the most sweet Lord. Once you have made this rule, you must force yourself to carry it out faithfully.My own spiritual father gave me this simple advice when I discussed this common problem with him, "Just decide to reject them! When you do, they will stop." Prayer involves giving your full attention to God alone.
From my personal experience, the practice of the Jesus Prayer in conjunction with controlling the thoughts is the essence of a fundamental spiritual practice that will lead you continually closer to God. Everything will follow with ease once you have engaged in a regular practice of the Jesus Prayer. Once the mind has been conditioned to remember the prayer in all situation, then God will be in your presence and there is time for you to listen to your conscience and to act with wisdom instead of passion.
More on the Jesus Prayer
Reference: The Spiritual Life, pp 198-200