The nearest major airport for Borisov is Minsk, the Belarussian capital, which is also conveniently where BATE play their European games. Flights to/from here are not exactly plentiful or cheap, however. Belavia fly direct from Gatwick, but pretty much any other departure point from the UK will require a connecting flight.
Sites like Skyscanner and Expedia will likely offer the best deals, and let you know what routes are available - it is possible to connect with Czech Airlines via Prague, for instance, or Lufthansa via Frankfurt, LOT Airlines through Warsaw or Aeroflot via Moscow among others.
If you're flying on a budget, check out connections through the Baltic states with Riga and Talinn offering flights to Minsk, too.
By Train
If you're scared of flying, or just fancy an adventure, check out the excellent guide to getting the train to Minsk from the superb seat61.com.
