I started off by making the heart for the top of my door. I made it by making a cube and flattening it out to the right thickness, I then extruded the sides and beveled them to make the two rounded bits. Using the edge tool I moved some of the edges around to make the heart shape.
I then made the shapes to go around the heart. I wanted it to look decorative like the kind of detail you get on iron gates. I made it using quite simple shapes, I used two whole cylinders and two cylinders cut in half .
Then to make the twirly bits I used a curve in the same way that I made my arch. I created the CV curve then extruded along it.