Stack together the sheets of paper, the number of which should be proportionate to the amount of batter you have, or the amount of muffins you intend to prepare. It is vital to make sure the paper is absolutely clean and free of toxins. White paper, food grade paper bags, parchment paper, or brown paper will work just fine for this purpose – just ensure that the paper you use is not covered in wax or plastic, and if kids want to decorate the exterior of the cup, make sure you place a plain muffin cup inside their decorated ones, in order to keep the marker ink from seeping into the muffin.
Place your stack of paper on a flat surface, and using your pencil, divide the paper into 4-inch strips. Then, using your scissors, cut these strips out.
Place your drinking glass on the strips, and trace around the outline with your pencil in order to create the muffin cup circles. Then, proceed to cut these out.
Put the muffin cup circles on top of the ¼ cup measuring cup, and force the circles in to the cup by pushing them in with your bottle. Use a reasonably thick stack, which will result in more uniform and even cups.
Finally, take the cups out of the measuring cup, and they are now ready for use. Be sure to spray the muffin tin with cooking spray or olive oil before you line them with your muffin cups, and any leftover cups can be stored in a cabinet for future use.