Conditions of Answered Prayer.

Have the faith of God:

Romans 4:17 

(As it is written, I have made thee a father of many nations,) before him whom he believed, even God, who quickeneth the dead, and calleth those things which be not as though they were.

Hebrews 11:3 

Through faith we understand that the worlds were framed by the word of God, so that things which are seen were not made of things which do appear.

Galatians 5:22-23 

22 But the fruit of the Spirit is love, joy, peace, longsuffering, gentleness, goodness, faith,

23 Meekness, temperance: against such there is no law.

Pray: say in no uncertain terms what you want:

Matthew 17:20 

And Jesus said unto them, Because of your unbelief: for verily I say unto you, If ye have faith as a grain of mustard seed, ye shall say unto this mountain, Remove hence to yonder place; and it shall remove; and nothing shall be impossible unto you.

Matthew 21:21-22 

21 Jesus answered and said unto them, Verily I say unto you, If ye have faith, and doubt not, ye shall not only do this which is done to the fig tree, but also if ye shall say unto this mountain, Be thou removed, and be thou cast into the sea; it shall be done.

22 And all things, whatsoever ye shall ask in prayer, believing, ye shall receive.

John 15:7 

If ye abide in me, and my words abide in you, ye shall ask what ye will, and it shall be done unto you.