There are many ways to trade your bitcoins. For you what is the best?
Well, your question is pretty broad so I'll answer it on a wide range.
Using bitcoin for trading altcoinsIf you are trading your bitcoin for altcoins especially before August the first to protect yourself, I would recommend depositing on Yobit, Polenix, or other exchanges to buy your coins off them. I wouldn't hold bitcoin on exchanges though since it would be unsafe.
Using Bitcoin for trading into Fiat If you want to trade your bitcoin back to fiat or if you have earn't some and you are now trying to exchange I would recommend exchanging it on localbitcoins.com since it is reputable. Do not trade for paypal unless they are trusted since you may get chargebacked.