The Foreign Office in London put out a statement which read: "Beer can be stronger than in the UK, so drink responsibly, know your limits and respect local laws. You may not be let into the stadium if you drink too much."
They also put out a line advising fans to get tickets only from official websites: "Only buy match tickets from official providers. Tickets will be electronic and you will need your mobile phone to validate them at entry. Make sure your phone is charged and take into account roaming charges in Germany – check with your phone provider before you travel. Match tickets bought through unofficial means may not be valid. If you sell tickets through unofficial means, you could be prosecuted.”