String of LED lights, small plastic bathroom cups, x-acto knife, double stick tape & pattern paper. Using plain paper, make a template. Cut pattern paper according to template and affix with tape. Use x-acto knife to cut an x in the bottom of each cup to push the light through. Change the pattern paper to match for the seasons/event.
Also on these boards
DIY Free Printable Tea Cups by Red Ted Art - Plaid Online