One thing that helps for me is to go to someplace other than home. Preferably someplace where I never or rarely engage in leisure activities so that I can associate it solely with studying. If you can get to your university's library, that's a great place since it just vibes "buckle down and learn your shit." Coffee shops can also work, or sometimes parks depending on the weather.
As a more random piece of advice: I know a guy that listens to Gregorian chants when he's studying and claims it helps him focus. Make of that what you will.
As a more random piece of advice: I know a guy that listens to Gregorian chants when he's studying and claims it helps him focus. Make of that what you will.