Step one:
First draw half an oval.
Step 2:
Then draw a rectangle up and down.
Step 3:
On top, draw a hook shape.
Step 4:
Draw two more arcs in the middle.
Step 5:
Draw another arc in the middle to form two lines.
Step 6:
Next, draw horizontal arcs, being careful not to cross vertical lines.
Step 7:
Finally, apply a nice color and the birdcage is ready.