A day trader often closes all trades before the end of the trading day, so not to hold open positions overnight. A day traders' effectiveness may be limited by the bid-ask spread, trading commissions, as well as expenses for real-time news feeds and analytics software. Successful day trading requires extensive knowledge and experience. Day traders employ a variety of methods to make trading decisions. Some traders employ computer trading models that use technical analysis to calculate favorable probabilities, while some trade on their instinct.
Individuals who attempt to day trade without an understanding of market fundamentals often lose money. Technical analysis and chart reading is a good skill for a day trader to have, but without a more in-depth understanding of the market you're in and the assets that exist in that market, charts may be deceiving. Do your due diligence and understand the particular ins and outs of the products you trade.
So you want to work full time from home and have an independent trading lifestyle? If so, you should know that turning part time trading into a profitable job with a liveable salary requires specialist tools and equipment to give you the necessary edge. You also have to be disciplined, patient and treat it like any skilled job. Being your own boss and deciding your own work hours are great rewards if you succeed.

Scalpers need to be disciplined and need to stick to their trading regimen very closely. Any decision that needs to be made should be done so with certainty. But scalpers should also be very flexible, because market conditions are very fluid and if a trade isn't going as expected, they'll need to fix the situation as quickly as possible without incurring too much of a loss. 
Scalpers buy low and sell high, buy high and sell higher, or short high and cover low, or short low and cover lower. They tend to utilize Level 2 and time of sales windows to route orders to the most liquid market makers and ECNs for quick executions. The point-and-click style execution through the Level 2 window or pre-programmed hotkeys are the quickest methods for the speediest order fills. Scalping is purely based on technical analysis and short-term price fluctuations. Due to the extensive use of leverage, scalping is considered a high-risk style of trading.
Originally, the most important U.S. stocks were traded on the New York Stock Exchange. A trader would contact a stockbroker, who would relay the order to a specialist on the floor of the NYSE. These specialists would each make markets in only a handful of stocks. The specialist would match the purchaser with another broker's seller; write up physical tickets that, once processed, would effectively transfer the stock; and relay the information back to both brokers. Before 1975, brokerage commissions were fixed at 1% of the amount of the trade, i.e. to purchase $10,000 worth of stock cost the buyer $100 in commissions and same 1% to sell. Meaning that to profit trades had to make over 2 % to make any real gain.
ECN/Level 2 quotes: ECNs, or electronic communication networks, are computer-based systems that display the best available bid and ask quotes from multiple market participants and then automatically match and execute orders. Level 2 is a subscription-based service that provides real-time access to the Nasdaq order book composed of price quotes from market makers registering every Nasdaq-listed and OTC Bulletin Board security. Together, they can give you a sense of orders being executed in real time.