Include sponsorship information and guidelines on your website to make it easy to deal with sponsorship and donation requests, and to showcase the causes you support.
Having sponsorship guidelines and information available is also a good way to handle or ‘qualify’ requests for sponsorship or donations. It can also provide a platform to showcase the causes you do support.
The Air New Zealand website's sponsorship page is great example of how to showcase the causes you support
Do you really need a sponsorship policy? – an excellent article outlining why sponsorship policies are valuable, and what to include in them