1. Keeping your Bitcoins in the exchange’s wallet
This is by far the most crucial mistake you can make. When you put your Bitcoins in the exchange wallet you’re basically giving up all control over them. If the exchange gets hacked because it wasn’t secured properly or even in the case of fraud (e.g. Mt.Gox, Inputs.io) you can lose all of your money. As soon as you get your Bitcoins, move them out of the exchange and into your own secure Bitocin wallet (e.g. Blockchain.info, Bitcoin-QT).
2. Keeping All of Your Bitcoins in One Place without Proper Security
Once you have your Bitcoins out of the exchange make sure not to put all of your eggs in one basket. If you have only a few then it’s not to bad, but if you’ve invested a considerable amount in Bitcoin it would be wise to spread them between different wallets. Also, make sure to properly secure your wallets so that they are harder to hack. One good idea could be to create a paper wallet and keep it somewhere safe.
3. Panicking Over Price Changes
Bitcoin is a currency, but not a very stable one yet. It’s very common to see price changes of up to $100 per day, so no need to panic each time you see a $30 drop. In a 2 year perspective, Bitcoin is gradually and consistently continuing to rise, even though there can be some ups and downs in the middle. After the first 2 radical changes you’ll get used to the fluctuation in this currency.
4. Skipping from one Crypto currency to Another
Every day another Altcoin comes out and people are all hyped about it. The problem is that most of these Altcoins aren’t as well established as Bitcoin and this can lead to fraud or just bad investments. To many Altcoin Pump and Dump scams are occurring and if you’ve just heard about Bitcoin then you’ve got more than a handful to deal with. My suggestion to you is to pick a coin you believe in (it may not even be Bitcoin) and stick to it.
5. Not Educating Yourself Enough / Listening to the Media
One of the main problems with Bitcoin today is that it’s not real easy to understand. For example, Googling the phrase “What is Bitcoin” will give you over 600 million results. If you really want to take your investment to the next level make sure to educate yourself at least with the basics (i.e. what is Bitcoin, Bitcoin mining, etc.). It’s also wise to get in touch with the Bitcoin community through the subreddit r/Bitcoin, Facebook Bitcoin groups and Google Plus Bitcoin groups. In 99% of the times these communities are one step ahead of traditional mass media channels.