When children make petition or request for a thing, they do so with confidence because they believe that they will not be turned down and that their request will be granted. The fear of rejection and doubt makes many adults reluctant to ask for help even when they are in need. In the same way children trust that their needs can be met by their parents upon asking, God, being our heavenly Father, expects us to approach him with such faith when we pray.
Some believers observe prayer as a religious ritual, however, and so they do not expect to receive. Prayer can be likened to a transaction; you must give something to get what you need. When we approach God in prayer and surrender to Him, we come to Him because we are convinced that He has the power to do what we ask; as long as our requests are within the confines of His divine will for us, we are sure we will get what we request. This belief and absolute trust in God's ability to do what we ask is the currency we tender to guarantee the answers to our requests. 
Apostle James tells us that a man who lacks faith will receive nothing from God (James 1:7). The next time you pray, make your request known to God as your Father in faith, just like a small child. You will receive what you ask for.

Dear Heavenly Father, I thank You for the opportunity to commune with You and make my requests known through the agency of prayer. I am grateful because You hear and answer prayer. Lord, I admit that there were times I observed prayer as a ritual and I am sorry. I ask that You help me be more intentional in my prayers. Help me to rid myself of doubt, worry and fear that has made my prayers ineffective. I place absolute trust in Your power to do all things and I believe there is nothing impossible for You. 
In Jesus’s name I pray. Amen.