The application shows a tiny panel on your desktop containing color selector, pen tip width selector and selector for pen or eraser. After the installation, it adds a new shortcut in your Start menu using which you can run it. The download is a little around 1 megabytes in size. The download is available as a setup installer. You can download Epic Pen from the sourceforge website. The drawing stays over the top of all the applications and therefore makes it very useful application for demonstration purposes. It is a software using which you can draw over your desktop in many different colors. I do not suggest you to use the marker pen on your computer screen, but you can use the freeware Epic Pen software instead.

But a better way would be to use something like a marker pen which can easily highlight what you are trying to say to the learners.

When showing someone how something is done in Windows, you usually either use your small mouse cursor or your fingers to point the things out to them.

Epic pen for windows