Formalising relationship with "Support Groups"

I have recently joined the MS Society primarily to support our branches with their fundraising.

We do have also a number of less formal "support groups" who regularly raise funds which they kindly donate to the Society.

We are exploring if we can begin to more formalise our relationship with some of these groups. Aims being to help clarify the position re PLI, use of logo, regularly donating funds etc.

Can anyone please point me towards any best practice?

Thank you