So, because he was of the same trade, he stayed with them and worked; for by occupation they were tentmakers. And he reasoned in the synagogue every Sabbath, and persuaded both Jews and Greeks.
Acts 18:3-4

While Paul worked with Priscilla and Aquila making tents to earn his living, Paul’s greatest passion was making disciples. Note two things about his method from (v.4):

He went to the Jewish synagogue every Sabbath day to reason with Jews and Greeks. Why the synagogue? Because Paul had a heart for his Jewish brethren. Paul was a “Hebrew of the Hebrews” (Philippians 3:5). He knew what it was like to know the Hebrew scriptures, that are all about Christ (John 5:39), without knowing Christ. But having come to know Christ, Paul longed to see more Jewish people know their Messiah. With that in mind, going to the synagogue was a wise choice.

He reasoned with those to whom he spoke. While the Gospel cannot be discovered through reason but must be revealed by the Holy Spirit, the gospel is not UNreasonable. We should know the gospel well enough to present it reasonably. Just as Paul sought to persuade those with whom he spoke, so ought we—knowing that it is as we speak (reasonably and persuasively), the Holy Spirit will save His people.

A footnote. Though Paul went specifically to where he knew he would encounter Jewish people, don’t miss the fact that his efforts were fruitful among both Jews and Greeks. This informs us that Paul did not speak exclusively with Jewish people, but with Gentiles as well. This reminds us that we are to pray for and proclaim the gospel to as many as we can, without respect to who they are—and that the Holy Spirit will save His people.