Its not wrong to say to earn through spot trading.
Think always before to buy trade. Here are few guidelines for you.
1. Always choose coin which is best that time
2. Go to loser coins which are going down, buy those.
3. List them with take profit what you can get by those coins
for example : you buy at the rate of 2.14 you can sell it 2.40.
4. Do not forget to add stop lose rate. The percentage you can bare. Suppose if you lose you will safe from big loose.