The easiest way to handle this when you don't have any investments, no professional liability or other complications, is simply that you set each your own individual sole proprietorship. Your friend, as he handles the administration, bills the client, and you bill him. Your agreement should likely be that you get paid when he does. This way, if things turns sour, you only stand to lose what your friend owe you - ther…
Having read the all the suggestions, this is the one I'd recommend. Partnerships are more bother than they are worth. There are a lot of IF's: If he brings in the business. If he does a "good" design. If he manages the client and responds to his calls. If he pays you on time. If he brings in clients that pay at the top end of the scale. Then he might be worth 50%. My impression is that your friend is trying to profit…
Agree on all other points.