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Please don't take this as snark but I wouldn't recommend shorting anything if you are so inexperienced that you don't have a trading account or don't know which one to use. Shorting stocks is extremely risky and should only be done by traders with lots of experience. If you really want to bank on Twitter going south, you can try buying puts when they're available. If you're not sure what puts are, leave this whole id…
i run a bootstrapped company that i founded in 2006, and i have some extra money i am totally comfortable of losing entirely. i view this as an experiment. i am looking for a serious practical advice.
Its been a while since I've dealt with IPOs so I'm not 100% sure if that's the case anymore.
If you want to get involved, call TD Ameritrade. They can give you 100% accurate information and get you setup quickly.