Take a walk through a park or forest, beach or mountain area for inspiration if desired. Bring a notepad with you to jot down ideas or landscape/wildlife scenes that you want to sketch. Make a list of specific themes you wish to incorporate into your poster, such as art inspired by sea life, green living ideas, recycling tips or simple slogans such as "Live Green" and "Plant A Tree."
Peruse internet quote sites for sayings by famous environmentalists like Rachel Carson or Seminole Indian Chief Osceola to use in a poster design. Use one quote, such as "Only When The Last Tree Has Died/And The Last River Has Been Poisoned/And The Last Fish Has Been Caught/Will We Realize That We Cannot Eat Money" over the entire poster board in assorted types of lettering or find several quotes. Paint or draw each quote in a different color and lettering style.
Draw or find pictures to go along with eco-themed words and phrases, such as "Make Art, Not Trash" with a famous painting transposed onto the poster board, "Recycle" with a drawing of the planet or photo of recyclable trash (for extra impact), or make a collage of pictures and photos. Collage ideas include pictures of endangered animals from around the world and pictures and photos of trash, the Gulf oil spill, smog from factories, and similar photos.
Draw or paint a landscape or ocean portrait with a picture of an endangered animal, such as a whale or dolphin swimming. The animal could be surrounded by trash, caught in a net or large piece of trash, or drawn as a beached animal if desired. Create jungle wilderness, draw mountain ranges, prairies, tundras or additional aquatic pictures with related animals. Leave the work as is or add a favorite environmental quote or saying.
Practice your design as many times as you see fit and make any corrections or alterations that are needed. Display your poster in your school or work, or donate it to an environmental group if applicable.