Because of Paul's statement in 1 Cor. 1:17 where he says, "Christ did not send me to baptize, but to preach the gospel" (NKJV) some have been inclined to believe Paul felt baptism was not essential. A careful reading of the context should make one reconsider. Just 4 verses earlier he asked the Corinthians to whom he was writing, "were you baptized in the name of Paul?" (1 Cor. 1:13 NKJV) Paul knew they had been baptized in some name for if they had not the question is foolish.
Just as Jesus is said to have baptized disciples (John 4:1) and we then read in the next verse, "though Jesus himself did not baptize, but his disciples" (John 4:2 NKJV) just in the same manner we suspect that in Corinth though Paul himself actually baptized very few personally (1 Cor. 1:14-16) yet the work was done through helpers of his and through other preachers and teachers. "And many of the Corinthians hearing Paul believed and were baptized." (Acts 18:8 ESV)