How can i prevent myself from depression?

Can't prevent: You can't completely prevent depression, but you can get diagnosed early and initiate treatment to help relieve symptoms and promote improvement. If there is concern, seek a counselor or psychiatrist for further evaluation and treatment planning.

Lifestyle helps: It's debatable whether someone who has a high risk of depression can completely prevent it but there are things that would likely help. Consider: regular exercise, healthy eating, connecting socially to family and friends, finding creative outlets e.g. Art, spirituality, and finding a rewarding job. An interesting, easy to read book on this may be the how of happiness by sonja lyubomirsky.