Qué estás haciendo?
What are you doing

Start it off with:

Yo haciendo
(I am doing) and just say what your doing.....Como las papas fritas (eatin french fries) that's a complete sentance. You don't need a paragraph.

If you want to make it longer just say....en la cafateria....Como las papas fritas en la cafateria (I'm eating french fries in the cafeteria)