I know for me that praying is often a struggle, I find myself continually fighting in this immeasurably important spiritual discipline. Here are some quotes that have helped me from godly men.
"Why will you run and labor and sweat and fret? There is greater benefit from striving in pray than from striving in the flesh." Paul Washer
"I know this to be true by the Word and experience. The return on our prayers is far greater than the investment made. Heaven will reveal it." Paul Washer
"The neglect of prayer is a grand hindrance to holiness." John Wesley
"The main lesson about prayer is just this: Do it! Do it! Do it! You want to be taught to pray. My answer is pray and never faint, and then you shall never fail." John Laidlaw
"Prayer can do anything that God can do. The pity is that we do not believe this as we ought, and we do not put it to the test." E.M. Bounds
"The prayer chamber, while it is the test of the sincerity of our devotion to God, becomes also the measure of the devotion." E.M. Bounds