What to do for 18th birthday?!
You should invite your friends over early, turn on some tunes, offer some snacks, and get ready together to go out. Everyone should bring their hair stuff, makeup, and a nice outfit.
Then everyone go out to a nice dinner together, somewhere that you can chat, laugh, and have a nice, relaxing, but still fun evening enjoying each other's company.
if you live in Vancouver BC, go to Crash Crawlies. It is super fun to enjoy doing with your friends. Filled with slides, crawling in tubes, rooms that have tons of plastic balls, lots and lots of excersise. Just be careful cause there might be tiny kids or babies near by. I know many friends that went there for their 18th birthday and they had a blast :)
Loves Crash Crawlies
It is best if you will go to beach and enjoy there. It is a nice idea also if you have your party in the house only. Less expenses and less danger also. I advice you to consult your parents also.
Haha i asked the same question 6 days ago :P jus get together with mates man get some bbq going or camping or find a spot to jus sit and drink leave the rest of the magic with alcohol :-P have fun!!!!
If you're in a cold state maybe some bowling or ice-skating? Midnight bowling was always fun at your age.