Best way to keep moisture in your hair longer

I'm sure you've read countless articles, tips, and recommendations on ways to keep moisture in your hair and so you might be led to believe that you know it all and don't need to read this. But I bet you've never read or heard this tip anywhere so it would be to your advantage if you read this post.

So, what's the best way to trap moisture in your hair for a longer period of time?
You simply KEEP IT BOUNDED!

Keeping the hair bounded means keeping it in styles such as twists, braids, flat twists and cornrows. I find that my hair feels more moisturized and soft in the days that I have twists in my hair. While on the other hand, the individual strands of my twist out, fro or any free form hairstyle often feels dry and straw like.

The reason behind this is quite obvious if you think about it. When the millions of hairstrands on our head are gathered into about 10-40 clumps, evaporation of water from each invidual strand is slowed down as water has to go through many layers of hair before escaping into the air. 
However, when the hair is out in it's free form, it's very easy for moisture to escape a single strand as oppose to having to go through hundreds of layers when bounded.

Analogy: You can compare this to the extra length of time it takes to dry 100pieces of clothing in the dryer versus 20 pieces. In a nutshell, you could say that "there is power in numbers"

Another way that I keep moisture in my hair longer is by wearing a plastic cap or bag over my head after moisturizing it. This plastic bag traps moisture in my hair and restricts the evaporation of water so that my hair is given enough time to absorb the products I've just applied before the hair dries up. I guess you can call it a "slow cooking" or "steaming" method.