It's better to store your bitcoin in your bitcoin wallet more safe and more trusted than investing but we know that now all cryptocurrency exchanger are trusted there are also exchanger that scam money when you do exchange.
Well probably choose the most reputable wallet in your country. For example here in the Philippines, I found it convenient to store my Bitcoins in Coins.ph. Or, you can make your own hardware wallet, or a paper wallet at least. I highly suggest not to put it in exchanger sites, you cannot guarantee that will not run in a long period of time.