Use reverse vesting and don't put provisions in that cofounders can't fire each other.

This will twist the incentives to align everybody.

  1. if you do 80% of the work and he does 20%, you can fire him and reap 100% of the rewards
  2. Same holds for you so it is fair
  3. The person who works the hardest will be the hardest to fire so if there is a big conflict the guy who doesn't work as hard will go. In case of conflict there is a lot of incentive to resolve it.
  4. This dynamic drives everybody to work really hard.
  5. Everybody will aim to make themselves as valuable as possible because there is essentially no downside to letting you go the first year. Doing valuable things will create downside for the company. 

You have to be bitten by this a couple of times before vesting starts to make sense, after all why would I not just get all my equity upfront. The worst I heard was a founder walking away with 30% of the company 9 days after the company incorporated.

Whether a business person will be able to contribute equally depends strongly on the type of project you start and where you are going to find customers.