Paul went 4-for-43 (.093) with two doubles, an RBI and 21 strikeouts as a pinch-hitter last year. He played 128 combined games with the Pirates and Dodgers in 2011.
"I struggled at finding a way to keep myself not just physically but mentally prepared to come off the bench and try to have success," Paul said. "For the most part, I just try to stay loose between innings, pay attention to the ballgame, to the pitching changes and study the relievers, closers -- the guys I think I may have a chance of facing."
Over his last 10 appearances, the 27-year-old outfielder is hitting .400 with a double. As a pinch-hitter, he is 10-for-29 (.345), which includes a single in Friday night's game.
Paul started the season with the Nationals' Triple-A club before his release on July 3. He signed with the Reds on July 12 and earned a callup from Triple-A Louisville six days later.
"A lot of it is just confidence," Paul said. "You get a hit to fall here or there, and you get that confidence. It's the same way as starting. When you're hitting the ball hard, you're the most confident guy. When you're not getting the hits to fall, it's easy to lose confidence. So I try not to let myself ever get too high or too low."
Paul singled in a pinch-hitting appearance during the 10th inning of Sunday's 5-4 win over the Marlins.