To earn a certificate from the NAA, you need experience and proper training. 1  1. Earn a high school diploma or GED. A college or university degree is not required to earn an apartment leasing agent certification. 2  2. Get at least six months of experience working as a leasing agent for an apartment community. Find leasing agent positions by perusing online job boards, or check out social media sites for apartment communities for job vacancies. Some apartment communities also post job vacancies on official websites.