Before you can design anything for your team, you need to know all about the history of your city.
Use these resources below to get a better sense of what your city is all about, and what your team uniforms/logos/mascots should reflect....
There are lots of uniform generators out there -- here are some to get you started!
Logos and mascots are also exceedingly important parts of all sports teams, and are developed/created with the team & city history in mind. Create yours accordingly!