Pay himself with the charities money, as he is an employee of the charity

Why does Bill Gates earn nothing through the Bill and Melinda Gates Foundation?

Lobby politicians using the charity’s money

A 501(c)(3) organization is subject to heightened restrictions on lobbying activities, A 501(c)(3) organization may engage in some lobbying, but too much lobbying activity risks loss of tax-exempt status. Lobbying may not constitute a “substantial part” of the activities of the 501(c)(3) organization. ^[source]

Otherwise direct the charity to work in his best interests

I guess you can argue that eliminating malaria is in his best interests, but it's pretty reaching. I guess nobody should do anything good if it might indirectly benefit themselves.