Start a chant. Make a noise. If no-one joins in, start it again. You might look like a twat initially, but persevere, if I hear it I'll join in.
Anyone can do it, don't rely on others, as we are usually incoherent by the 2nd half.
(Ditch the beer, drink red wine)
Take people along, if you take 10 people, 2 or 3 might come back regularly!