You would use a mathematical application like Geogebra, you can directly introduce the equation of the Parabola or create it using its focus (F) and its linear directrix (H). Using the relation: "any point P on the parabola will be equidistant from both the focus and the linear directrix".

You can use another mathematical applications, but Geogebra is the most intuitive and you can introduce an equation to be drawed or draw directly in the cartesian plane. And you can export your drawings as an image or an interactive applet.

In Geogebra is possible to create another geometrical entities as lines, points, circles, etc. and create another ones using intersections, angle and linear segments bisections, etc.

I am a math teacher and a programmer who teaches my students Geogebra as a tool for learning Mathematics.