A. Scan for stocks the night before based on whatever criteria you look for. Have your stocks picked out before the market opens with set entry points such as "if stock ABC reaches x price I'm going to buy/short." B. Have a few select stocks that you always watch, and watch them throughout the day, entering when you see setups that look like they will be winners. For example "I keep an eye on ABC and when x situation occurs I buy/short, regardless of what it did the day before or what the price is." C. Something else (explain if you want).