And Solidarity was the movement that brought down the communism in Poland and in fact in the entire Warsaw Pact.

Through generally non-violence (in face of violence, including many of assassinations and other killings by the government). Some people tried hijacking planes (the early 1980s was the period when Poles were hijacking more planes than the Palestinians) or things like the Polish embassy in Austria being taken hostage, but this wasn't what did work out. There was also quite a lot street fights but just with stones vs tanks (https://youtu.be/7si5Dphr8co - note how everyone participating is unmasked, unlike these Antifa cowards in America). A few young people also went to fight the Sovietoids in Afghanistan, among them the future minister of defense Sikorski (and one died there by being in fact murdered by Hekmatyar's guys). But really it was just the mass non-compliance and strike actions that broke them.

Besides years of very crippling economic sanctions by President Ronnie, following the military coup intended to crush Solidarity: https://youtu.be/vSkTbyDqdH4