There are lot of common mistakes every trader do when they are new. I also did the same. Like opening trade position before big news events and after the news events. Opening too many lots is another mistakes. Risking more than 1% of the capital is also a mistake. Another big mistake is unrealistic expectation. We come here to make double, triple of our capital over night. But it's the biggest mistake one can have. We also make mistake in choosing broker.
Sometimes from the mistake, we can learn something then, and after understanding the mistake than trying to make new rules how to avoid the same mistake not repeated again, but sometimes the hard part is how to control our decision, fear missing out, become a common problem during the trading time, choosing broker indeed very important for a trader.