Let’s start from the very beginning, before you even wash your hair. Instead of jumping straight in, brush your hair before you wash it, this will help you in the long run and will help get out any tangles.
When you are washing your hair, make sure that you are using a shampoo that is good for your hair type. On top of this, make sure that the shampoo is meant for daily use.
Avoid using conditioner! This will weigh down your hair and your hair already gets enough oils from your scalp, avoid it. If you MUST use conditioner, and by this I mean if it is unavoidable, then use a small amount, don’t use it everyday, and only use it on the tips of your hair. The root of your hair doesn’t need the oils, they already have them.
Check out these volumizing conditioners if you must use conditioner.
When you are drying your hair, dry it upside down. Try avoid blow drying your hair for the most part, try towel drying instead. This will add a lot of volume to your hair.