From my experience:
- make sure scalp is always healthy, if unhealthy and oily, will feel itchy, hair fall is more and hair root kena block, susah to grow balik
- have sufficient amount of sleep
- drink enough water
- avoid oily/spicy/salty food especially if got ajinomoto
- maintain a healthy diet and exercise, protein is essential for hair growth btw
- don't comb your hair when it is wet, especially the forehead there, you don't want to have M-shape like me
- not scientifically proven yet but I think radiation from computer/laptop/mobile phones contribute to hair loss
- try to avoid chemical based shampoos if possible, go for herbal based shampoos instead

Currently I'm using Ecoherbs, quite pricy but it does make my scalp feel refreshed and got cooling effect. Used to have a little bald spot at the centre of my head but now no more edi. My M-shape still cannot solve though. My advice is don't spend unnecessary money visiting big hair care centres, it can easily reach thousands and they will keep recommending expensive treatments and products. Unless you're loaded, then different story.