My strategy is to daven as fast as possible. If I daven slower, I may start off with kavana, but space out at some point. By davening quickly, I’m forced to keep track of where I am, and I don’t get bored.
Davening doesn’t have to be from a siddur. Asking Hashem for help on a test, or thanking Hashem when you did well or are happy about something, is also davening.