Most look the age at which they 'discovered' immortality. As others said, we are not necessarily talking 100% immortals, just people who have drastically slowed down aging. There are actually many many types and colors of immortals... I heard from reliable sources of people who look 60 when they are 300. I met one guy who looked 30... but I knew he was much older. My teacher refused to tell me how old he was. lol.

Then there are those who can incarnate at will, and disincarnate again whenever they feel like it. But there are rules governing how, why or when they interact with people. Contact is rare. At least for me, it is right now...