1. Remove the ink from the pen so it's just a hollow tube. 2. Cut the cotton swab in half so it's a ball of cotton at one end and a stick at the other. Handy tip: Cut the stick at an angle, because you're going to have to push it into the end of the pen, and the swab's stick is probably thicker than the pen's opening. Cut the cotton swab at an angle so it can fit in the tip of the pen more easily.Dave Johnson/Insider 3. Force the cotton swab into the pen so that the cotton sticks out where the ink tip used to be. Push the cotton all the way to the tip of the pen. If it's loose, use a little tape to hold it in place; otherwise, let the tension hold it in place.