Disclaimer: I am not a lawyer nor an accountant, and this is not "professional advice."

I have, however, set up a few businesses and had partners.

What you need to do is incorporate and then write up an Operating Agreement that lays out the terms of your partnership.

Who owns what.

How the new partner will "buy into" the organization with their sweat equity.

What happens when revenue targets are reached.

And how exactly you separate when it's time to move on.

Lay these details out and more in your operating agreement. You'll be so happy you did, later.

When you incorporate, you may do this on your own...or you may want an attorney or accountant to help. They will know how to set up an operating agreement, but now that you know the term it's likely you can google a template. There'll be a lot of technical mumbo jumbo in there you probably won't need, but the section headers will guide you in the right direction.