What do 2600 level grandmasters do to earn a living? I want to know what a grandmaster does to earn a living, because if he has a 2600 rating then he is not able to win many tournaments.
I believe you meant a rating of 2600 not 1600, the most common way is Coaching. Coaching rates can be as high as 100 usd per session(1.5-2hrs) with a grandmaster of that level or as low as about 35-40 usd(each session).