Me too I don't know when a coin price increase or decrease. One thing I know if that coin has the potential therefore it will increase and if they have a lot of supply I think the coin price will decrease
We cannot predict coin price if dump or pump but you can research its price in the coin market cap statistics so that you can get more information about its price increase,because coins price increase is depends in the market supply and if the coins has a high demand the price will surely increase and you can choose a potential coin so that you can get benefits,and also study the trading statistics because it will help you to get a lot of information to become successful traders.
You can predict future pumps and dumps by knowing some things before others. You can predict things, or be close to it if you follow what is happening here in crypto. Upgrade announcements, some new things, new contracts, adoption in some sector are driving price up, same like bad news are driving the price down, knowing news before others and knowing what kind of impact they will have on community and people generally can make reading the future more correctly. How to know something before others, follow people who knows people, they tend to know things better and read what they say between the line, try to sense when something good is ready to make it happen, same like to have sense to feel some upcoming problem and to use that in your advantage.