How soon was Paul baptized after God called him?
"And now why are you waiting? Arise and be baptized, and wash away your sins, calling on the name of the Lord" (Acts 22:16 Acts 22:16And now why tarry you? arise, and be baptized, and wash away your sins, calling on the name of the Lord.
American King James Version×).
After Christ appeared to Paul on the road to Damascus, He sent to him a man named Ananias who spoke the words above that Paul might regain his sight, be baptized and be filled with the Holy Spirit (Acts 9:17-18 Acts 9:17-18  And Ananias went his way, and entered into the house; and putting his hands on him said, Brother Saul, the Lord, even Jesus, that appeared to you in the way as you came, has sent me, that you might receive your sight, and be filled with the Holy Ghost.
 And immediately there fell from his eyes as it had been scales: and he received sight immediately, and arose, and was baptized.
American King James Version×). Paul was baptized immediately.
Sometimes people delay baptism because they think they must first become perfect. Others think they have not learned enough. But such reasoning is incorrect. The Scriptures record many examples of people who, when they heard the truth of God explained, saw their need to be baptized immediately (Acts 2:41 Acts 2:41Then they that gladly received his word were baptized: and the same day there were added to them about three thousand souls.
American King James Version×; Acts 8:12-38 Acts 8:12-38  But when they believed Philip preaching the things concerning the kingdom of God, and the name of Jesus Christ, they were baptized, both men and women.  Then Simon himself believed also: and when he was baptized, he continued with Philip, and wondered, beholding the miracles and signs which were done.  Now when the apostles which were at Jerusalem heard that Samaria had received the word of God, they sent to them Peter and John:  Who, when they were come down, prayed for them, that they might receive the Holy Ghost:  (For as yet he was fallen on none of them: only they were baptized in the name of the Lord Jesus.)  Then laid they their hands on them, and they received the Holy Ghost.  And when Simon saw that through laying on of the apostles' hands the Holy Ghost was given, he offered them money,  Saying, Give me also this power, that on whomsoever I lay hands, he may receive the Holy Ghost.  But Peter said to him, Your money perish with you, because you have thought that the gift of God may be purchased with money.  You have neither part nor lot in this matter: for your heart is not right in the sight of God.  Repent therefore of this your wickedness, and pray God, if perhaps the thought of your heart may be forgiven you.  For I perceive that you are in the gall of bitterness, and in the bond of iniquity.  Then answered Simon, and said, Pray you to the LORD for me, that none of these things which you have spoken come on me.  And they, when they had testified and preached the word of the Lord, returned to Jerusalem, and preached the gospel in many villages of the Samaritans.  And the angel of the Lord spoke to Philip, saying, Arise, and go toward the south to the way that goes down from Jerusalem to Gaza, which is desert.  And he arose and went: and, behold, a man of Ethiopia, an eunuch of great authority under Candace queen of the Ethiopians, who had the charge of all her treasure, and had come to Jerusalem for to worship,  Was returning, and sitting in his chariot read Esaias the prophet.  Then the Spirit said to Philip, Go near, and join yourself to this chariot.  And Philip ran thither to him, and heard him read the prophet Esaias, and said, Understand you what you read?  And he said, How can I, except some man should guide me? And he desired Philip that he would come up and sit with him.  The place of the scripture which he read was this, He was led as a sheep to the slaughter; and like a lamb dumb before his shearer, so opened he not his mouth:  In his humiliation his judgment was taken away: and who shall declare his generation? for his life is taken from the earth.  And the eunuch answered Philip, and said, I pray you, of whom speaks the prophet this? of himself, or of some other man?  Then Philip opened his mouth, and began at the same scripture, and preached to him Jesus.  And as they went on their way, they came to a certain water: and the eunuch said, See, here is water; what does hinder me to be baptized?  And Philip said, If you believe with all your heart, you may. And he answered and said, I believe that Jesus Christ is the Son of God.  And he commanded the chariot to stand still: and they went down both into the water, both Philip and the eunuch; and he baptized him.
American King James Version×; Acts 16:30-33 Acts 16:30-33  And brought them out, and said, Sirs, what must I do to be saved?  And they said, Believe on the Lord Jesus Christ, and you shall be saved, and your house.  And they spoke to him the word of the Lord, and to all that were in his house.  And he took them the same hour of the night, and washed their stripes; and was baptized, he and all his, straightway.
American King James Version×; Acts 18:8 Acts 18:8And Crispus, the chief ruler of the synagogue, believed on the Lord with all his house; and many of the Corinthians hearing believed, and were baptized.
American King James Version×).
Being baptized and receiving the Holy Spirit are the beginning of a new life in Christ. We should request baptism as soon as possible after repenting. Once we understand that our previous way of life needs to be changed and we sincerely want to change it, we must have God's help to go forward. We receive that help by being baptized and receiving His Spirit.
With whom should we counsel for baptism?
"How then shall they call on Him in whom they have not believed? And how shall they believe in Him of whom they have not heard? And how shall they hear without a preacher? And how shall they preach unless they are sent?" (Romans 10:14-15 Romans 10:14-15  How then shall they call on him in whom they have not believed? and how shall they believe in him of whom they have not heard? and how shall they hear without a preacher?
 And how shall they preach, except they be sent? as it is written, How beautiful are the feet of them that preach the gospel of peace, and bring glad tidings of good things!
American King James Version×).
Since baptism is one of most important actions we can ever take in this life, we should be sure to counsel with a minister who is truly "sent" by God—a minister who faithfully teaches and practices keeping all of God's commandments and correctly understands the teachings of the Scriptures.