Typically just go downtown.. find my self a good spot and sit and watch the fireworks. Then struggle with the mass crowds all trying to leave at the same time.
Depending on the city. The city I live in used to put on a huge massive concert every year with some big name Canadian artists. That changed a long time ago though.
I am Canadian! Remember those commercials? The beer commercials were always the best. Life in Canada usually revolves around beer and hockey, and on Canada Day we throw in some fireworks.
Most people just party, but there's usually alot of parades and other stuff going on in every city. I get together with a group of friends ever year and we make a huge tower out of empty beer cans at a local nightclub. The other customers at the club pay for the beer and put in donations. The bar puts $1 for every can towards a local childrens charity. Every year we have to make it bigger than last year (we did almost 500 cans last year). And of course, you can only put a can in that you have drank yourself Last year we had people coming by and dropping $20 at the table just to watch us chug 20 cans of beer then try and get them onto the tower without knocking it over. Gets really interesting after everybody has had 30+ beers Customers get a good show, the bar makes a huge amount of money, a children's charity rakes in a few grand (last year we had $500 from the beer purchases, plus $2400 from donations), and we get drunk essentially for free since the other customers are paying for it. All good fun, and everybody wins