Get assistance in the following ways:
You can print a small proof of your poster by printing as you normally would. Just be sure to check Scale to fit paper in the print dialog box. Otherwise only a portion of your poster will be printed.
Often colors in PowerPoint look very different on the screen than they do on paper. It is advisable to convert your poster to a PDF file before submitting it to a printer.
These online printing companies offer free research poster templates, fabric posters (for easy folding and transport), and fast turnaround time.