Brainstorm ideas for your sports banner's design and text. Develop a list of things that makes your team special which could be used to create a tag line for your banner. For example, if your team's players practice extra hard, then expressions like "110 Percent" or "Over the Top" could work.
Take one or more photos of athletes on the team or a group photograph for placement on your banner.
Gather elements together that you will need to give to the company that will print your sports banner per your specifications. Some office supply chains offer professional design and printing services for a variety of materials, including banners of different sizes.
Create a rough version of your banner by either sketching out the design with added text on paper or by using cutout letters along with photos to make a mock-up. Tape items to a sheet of paper that matches the proportions (if not the scale) of the banner you require. For example, you may have several photos that you want to use together in a collage design beneath the name of the team and above the slogan or tag line that you have created for your team.
Take your sketch or mock-up, along with the text files and images, to the service you have selected to put your design in a format that can be used to print your sports banner.