1. Prepare Tianzhuo quick-drying gel pen and the applicable refill.
2. unscrew the tip of tianzhuo quick-drying gel pen clockwise.
3. Pull the refill out of Tianzhuo quick-drying gel pen.
4. Insert the new refill into the case of Tianzhuo quick-drying gel pen, and screw on the pen tip, rotating counterclockwise.
Please note that different signature pens may have different ways to change the refill. It is suggested to choose the appropriate way to change the refill according to the actual situation.