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The advice I gave myself in these 2 weeks is that If any of my coin investment is going low in price, I just need to hold and wait for it to come back at the profit level.
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Don't do the above, this is very risky for beginners, it would be better if you want to invest so just buy top coins and learn market movements with your technical analysis knowledge. If you want experience then you can do it because who knows it will make a good profit, but I have to say that the risk is huge and takes up a lot of your time. Maybe my advice is to enter a market like xrp, btc and some other altcoins that have manipulative markets. The market will force you to move with dominance demand, this is very good for trading experience and you can understand to choose a good market, this is a bit extreme but in my opinion it is worth it. While here many users have already provided advice on trading basics, strategy and management planning.
I agree, the idea of holding your coins no matter what could apply to bitcoin and maybe to ethereum as well but I will not apply that strategy to any coin that has less than five years in the market, it is simply to risky for any investor and as you may guess that strategy is even more risky for newbies that do not really know what they are doing.
But I know that those newbies are never going to listen to that advice, despite their lack of knowledge they are full of confidence and they think they know better and while that kind of attitude can be positive in many aspects of your life when it comes to trading for the most part it leads to huge losses.