Each time, before you intercede...

"Beware in your prayers, above everything else, of limiting God, not only by unbelief, but by fancying that you know what He can do. Expect unexpected things, ‘above all that we ask or think’. Each time, before you intercede, be quiet first, and worship God in His glory. Think of what He can do, and how He delights to hear the prayers of His redeemed people. Think of your place and privilege in Christ, and expect great things!"
...Andrew Murray