Summarize this article:

A bottle with a plain top and sides will work the best, but you can use other types too if you don't mind the molded designs. For the most realistic trophy though, you should use a 1.5 to 2-liter (50.7 to 67.6-fl oz) soda bottle.  Make sure that the bottle is empty and clean. If it's dirty, fill it with water, then add a pump of dish soap. Close the bottle, shake it, then pour the water out. Make sure that you remove the label as well. If there is any residue, use a goo-removal product to get it off, such as Goo Gone. You can use spray paint for this or regular acrylic craft paint. Most trophies are gold or silver, but you can make yours any color you want. Apply 1 coat of paint first, wait 10 to 20 minutes for it to dry, then apply a second coat and let it dry too.  Apply acrylic craft paint with synthetic taklon brushes. Avoid bristle brushes (too coarse) and camelhair brushes (too soft). If you are using spray paint, be sure to work in a well-ventilated area. Apply the paint from 6 to 8 inches (15 to 20 cm) away. If you want a more elaborate trophy, consider painting some words or designs onto it, such as "#1" or "Champion!"  Alternatively, draw your designs with hot glue before you paint the trophy. This will give you nice, raised designs.

Summary:
Get a clean, empty plastic bottle. Paint the trophy your desired colors.