If your winners are larger than your losers on average your in good shape. I have no problem making $100 to $200 (I'm only trading one contract) most days but every few days I will lose $300 or $400. Sometimes this will happen a couple of days in a row and your down for the week. You can only settle for $100 to $200 a day if your losses are averaging around $50 to $100 a day and I find this nearly impossible trading the eminis. They can move against you so fast that you can be down in a hurry. If you set your stop that tight you get stopped out all the time. I must make more money when a trade is going my way. I have widened my stop to 3 pts on ES and 7 pts on NQ and checking my position every 15 minutes and trailing a stop and staying in the trade until I get stopped out. Only been doing this a few days but I feel I'm on the right track. I've stopped trying to scalp and am concentrating on trades that have the potential to move a decent amount to get my risk/reward more in line.
Successfully trading around a position will of course require full attention on an intraday basis, but I think "learning how to stay in longer" will only apply to trades initiated which would naturally encounter one or more pullbacks on the way to that trade's ultimate objective -- trades which would more likely last from an hour to several days. I think if one is initiating trades for .10-.50 gains per trade on a stock which normally has say a $2 range, you should most likely always sell out the entire position if you feel the position is about to turn, as the benefits of scaling on such a tight level is minimal to none. Just because a stock runs $3 past your .50 scalping gain doesn't mean you should have "learned" to hold longer; just as a climax bottom buyer who catches a 10% move on a multiday bounce would not look back at the stock one month and 20 points later and think, gee, I should become an investor since I missed those extra 20 points -- it's a totally different game at that point. Learning to hold winners longer is a skill everyone wants to improve on; however, eventually you reach objectives/time frames that go beyond the type of trading you're accustomed too. This is why its difficult to go from scalper to position trader and vice versa -- one must accept the dis/advantages of either style and realize its near impossible to get the best of both worlds.
I usually use a trailing stop via a price alert (on TS6) and cover my initial cost as soon as possible such that I get out at a breakeven in a worst case scenario. Depending on the stock and the time interval you're using, set your alert to allow for some wiggle room. Do I always get out at the top if I'm long or at the bottom if I'm short ? Absolutely not, but I usually get the majority of the move and thats fine for me. I also try to trade in the same direction as the market and/or sector whenever possible. Good luck.