You can try doing the following:
1. Avoid substances - Alcohol, cigarettes, drugs etc.
2. Healthy nutrition
- Limit processed goods.
- Aim for 35g of fiber mainly from fruits and vegetables
- Try to have 1.6g of protein per kg of bodyweight
- Drink plenty of water.
3. Exercise
- At least 2x/week resistance training that ideally train the major muscle groups (i.e. a hip hinge pattern, vertical/horizontal push, squats, vertical/horizontal pull).
- Aim for 150 minutes of cardio a week (typical heart rate to aim for is around 120bpm for most adults OR a pace where you can comfortably hold a conversation with someone)
4. Social groups - Surround yourself with trustworthy people.
5. Sleep - Aim for 7-8 hours a day.
The things listed above are already difficult to do, and depression makes it even more difficult especially the more severe the depression is. Even if you do all of the above, there is still no guarantee that you will be free from depression. But there's no doubt it will help.
These are health promoting lifestyle changes you should make (if you care about your health) because it greatly reduces the risk of just about every illness. Take note, I said it reduces the risk of illness (i.e. lower probability), I didn't say it prevents illness.
If all else fails, seek help from a medical professional.
And for believers and non-believers alike, offer your difficulties to God and trust that He is always there for you.
