For many of us, it is hard to have kavanah sometimes while praying. And sometimes we have it more than other times.
I think that inorder for us to improve in our kavanah, we need to work on strengthening our relationship with Hashem first. We should each find our own thing to help us with this. For example, it can be working on personally talking to G-d while in your room or somewhere else, or we can use song and sing from the heart which helps to lift us up, or we can make a list of things we're grateful for having, etc. This way we strengthen our connection to Hashem and improve our kavanah.
What so important about this closeness? It's because deep down, this is what our soul needs. It doesn't want to be caught up in the sea of materalism. It wants to be connected to it's Source. Thus we have Torah, mitzvos, and prayer to do that. And there are, within Jewish law, many different ways to do it. - Growth is not meant to be easy, but take effort, because then it is internally rewarding. It's kind of like receiveing an A in calculus.
Our mission here in this world is to spread goodness in the world and connect to Hashem. Of course, sometimes we mess up because we're human. However, we can and should pick ourself back up and go forward.
Speaking of what I mentioned above about music, here's a video below of a kumzits. It reminds me of when me and my girlfriends to use sing together at my friends house. This vid is of the Yaakov chesed band and their friends.