Train as many troops as you can. The total might of the troops you train contributes to your score. Inventory troops opened does not contribute to your score
You can train your troops by tapping on the barracks.
Once the barracks window opens you can tap on train troops.
Here you can choose the troops you want to train and the quantity that you need.
For training wall defense you need to tap on your wall to open the window
From there, tap on train defense to choose which you would like to get.
To open your inventory troops. Go to Items and check on the combat tab to find them.
Remember, the more might you add the higher you will place.