Buying a put is hedging. You won't lose as much if the market goes down, but you'll still lose capital: lower value of your long positions.
Buying an ultrashort like QID is safer than shorting a stock because you don't have the unlimited losses you could have when you short a stock. It is volatile. It's not a whole lot different than buying a put; it uses futures and swaps to give the opposing behavior to the underlying index. Some places indicate that the tax consequences could be severe. It is also a hedge if you don't sell your long positions. QID opposes the NASDAQ 100 which is tech-heavy so bear (!) that in mind.
Selling your long positions gets you out of equities completely. You'll be responsible for taxes on capital gains. It gets your money off of the table, as opposed to playing side bets or buying insurance. (Sorry for the gambling analogy but that's a bit how I feel with stock indices now :) ).