Covering Spreads in Day Trading involves the purchasing of a stock at the bidding price and selling the stock at the asking price, which results in a difference of monetary value between the bidding and asking price; this difference is the spread.
The larger the spread the more potential for profit from that particular stock and vice versa. Covering the Spread involves just purchasing at the bidding price and selling at the asking price. Even if there is no movement, this process still fosters and can foster significant profit.
Due to the quick nature of Day Trading, this process is, most often, the safest and most intelligent way to earn a daily profit, though the gains would not be as high as the riskier methods and strategies of Day Trading.