Answer/Explanation:
In this situation, there are several ways you can adjust your work. A few is highlighted below.
1. Adjust front size: depending on the program you're using for your design, I this case which I assume is a word document, u may slightly reduce the font size of either the headings, the bold texts or the entire text on the poster. This should ensure the texts fit to one page and the font size is not too small for legibility.
2. Adjust page layout: at the top and sides of the paper, you can slightly adjust the width and height of the paper to be wider and/or higher; to make all text fit into a page.
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