Let your skin adapt gradually
Play short, regular sessions rather than pushing through sore fingers. Use only the pressure needed for a clean note; pressing as hard as possible is not the goal.
Care for your fingertips
Pause if skin becomes sore and do not play on an open wound or blister. Dry your hands after washing before playing. You do not need to sand your skin or artificially build calluses.
Are calluses required?
No. Fingertips may adapt over time, but clear playing relies more on technique and a playable instrument.