The important thing is that you have a plan for how much money you want to invest in the coin. For example, you want to use $10 to invest in that coin. You can buy it at current prices for $2-$3 or even $5.
But it's best not to buy an all-in with $10 right away because if the price keeps dropping, you can't buy it anymore. Usually, I'll place a buy order 3 or 5 down the line from the buy order and wait for it to fill. And if the price continues to decrease after that, I will place a buy order on the bottom 5 rows again.
But it's best not to buy an all-in with $10 right away because if the price keeps dropping, you can't buy it anymore. Usually, I'll place a buy order 3 or 5 down the line from the buy order and wait for it to fill. And if the price continues to decrease after that, I will place a buy order on the bottom 5 rows again.