ironchef is correct. Options prob not the optimal way to daytrade tickers. IF YOU MUST, your best bet is to do an ATM vertical where both legs straddle the current price. It is most likely the most liquid, and the least exposed to the other greeks (theta,gamma, vega)- the closest delta play you can have. That means however, that you can't count on theta to enhance your return.BUT since theta is not an issue as much, this means you can avoid the entry on thursday , exit on friday thingy... 
