To trade in the day you must know technical analysis. When you know technical analysis you will know the points buy and sell in the day to be able to get profit.
Day trading is a tough job and not easy, Day trading require to me more active and study the market regularly. In day trading you need to take a quick action, if you will delay you can certainly lose your investment in minutes. While in long term investment you have to wait for better time to sell your coin, long term investment is comparatively easy and less risky.