For momentum day trading concentrate on a few stocks and know their chararacteristic behaviors.

I've been day trading for 2 years now, technical analysis means nothing, the guys who look at charts all day don't make any money. To be a good day trader you can't have an opinion, you just react and go with the momentum. Sticking with a handful of stocks and getting to "know" the specialist and his market are far more useful.

I generally trade the same few 4-5 stocks everyday, if I buy a stock and it doesn't go up while the market does/or doesn't I just view it as a mistake, I did not have everything foing my way or I am out of synch with the market. What you will find though is that if you trade the same stock(s) everyday you will get a very good feeling for how they trade, this again gives you an advantage over those individuals who trade every stock known to man.