To add your logo, go to the setup icon and under site settings select settings. Now select the branding tab. You will see that you can add/replace your logo, or add a text version of your club name if your logo is not yet available.
To add a text version, click the text only option highlighted in blue:
Then type in your club name and click the apply button at the bottom of the screen.
To upload your logo, you can either drag it into the empty box, or click find it here, and search for your logo on your hard drive.
Please make sure your logo is a JPEG, EPS or PNG. It should also be no larger than 900x400 pixels. Once you are happy with your logo click apply.