Keep your money in wallet
UPD (June 1, 2018): To date several more wallets and exchanges have added SegWit, including Bitcoin Core, BitGo, OpenBazaar, mSigna, Edge, KeepKey, Kraken and Bitso.
The popularity of centralized exchanges among users is proportional to the bitcoin growth. Despite the fact that nobody knows precisely how many users keep their funds on exchanges, we can say that the number of these people is growing. Moreover, the bigger the exchange, the more attractive it is for hackers.
So, it is time to remember basics of security. When it comes to bitcoin, you should trust its safety to no one. The only reliable tool is the private key. If your key is safe, there are bitcoins. If not, there are no bitcoins.
This truth seems to be very simple, but even the most experienced bitcoins holders forget about it and face bad consequences. Only you should know your private key; reliable exchanges do not exist.
The funds that you keep on the exchange do not really belong to you. If the exchange loses your funds, you have no way to get them back. As of now, there are no legal instruments for that.
If you are lazy to do it, remember what consequences those people who had already committed such mistakes faced. In 2014, Mt. Gox was hacked, and 850,000 bitcoins were stolen. In 2016, Bitfinex was hacked with 119,756 bitcoins. In 2017, the largest exchange BTC-e collapsed. Users of these exchanges were likely going to withdraw money from day to day as well, but they eventually failed.
Keep your money in the wallet that supports SegWit
Unfortunately, not every wallet will suit you. While the number of transactions in Bitcoin network is growing, the speed of transactions is slowing. You have to pay a significant commission fee for accelerated transactions. That is why choose services that support SegWit.
SegWit is the backward compatible protocol upgrade that was initially proposed by Bitcoin Core development team. It became a part of the “New York Agreement," an alternative scalability project, signed in May by 56 companies and miners.
It reduces the virtual size of transactions and increases block capacity by four times. Even if you pay for transactions, you save 30%–40% on commission fees by using SegWit.
There are no drawbacks of SegWit wallet yet; on the contrary, there are only benefits. These wallets give the potential to network scalability, help to save on transaction commission fees, and reduce the network load.
Here is a list of wallets that have already added SegWit: Bitcoin Core, Ledger Nano S, Trezor, Electrum, Armory, Edge, GreenAddress, Samourai Wallet, GreenBits. If the wallet you use now does not support SegWit, it is better to change it.
Moreover, it is better to exchange your money on exchanges that use SegWit, for example, HitBTC, ShapeShift and Bitstamp.
Now, when you have sent your money to a trusted wallet that supports SegWit, you can sleep well. Your bitcoins are safe.