Assuming some of us are newbies asking this quesiton:
Trading takes a lot of time to learn. As much as what it takes to be a lawyer or an MD. Some may get lucky in a few bull years starting out luckily at the right time, but without experience in dealing with losses they eventually will get wiped out when market turns.
Scalping takes a lot of energy and concentration. Full time. Fast reaction required. You need to deal with taking losses as well. Winning scalpers are usually very smart and quick. How long can they sustain in the game, I always wonder. They sleep better at night. They can wake up any time to enter the market and trade.
Swinging is for a more cautious and analytic individual. Dealing with charts, fundamentals, correlating market indexes into the trade takes a different amount of time, and you deal with the stress requiring your full attention of the market 24/24. This could be stressful.
I recommend a full time job swing shift, and scalp in the morning. This way, you can put your hear at work, deal nicely with bosses, coworkers, no stress, take home some 50K a year, and scalp in the morning for another 50K a year. eventually, you might be able to bring in hundreds K every year, and still sleep better at night. Key to good life is a straight stress free 8 hours of sleep. If you aim for making 100K a year by trading, you probably will lose money and your precious time. Not worth it.