How to better manage a project?

How can we manage and better organize out project? We would be more like a non-profit organization (we would get money from grants and donations) but do we need to create a formal NGO or can we manage informally?
Could we partner up with an existing NGO/Company, give them 5% of all donations and cut the overhead/administrative cost?
Does anyone have experience with this? Is there a case study that we can research upon?