Mostly 100 shares if I'm not scalping. Sometimes i let a position grow in share size, but usually in increments of no more than 200 shares per order. I've said it before, I'll say it again: I'm a little guy. But the way the market is right now, I don't think I'm missing out on too much by being cautious and remaining in the "testing and training" stage for a little while longer.
It depends on the price of the stock. If its EBAY right now 500 to 1000 but a lower priced stock 2000 to 5000. I like to swing 10,000 to 15,000.
100-200 shares ...although everything is so cheap now it's a wonder everybody isn't trading exclusively in 1000 hare blocks