By best, I mean good in any way like reliability, speed, convenience.
Sometimes an escrow may be the best way.
But then there are OTC markets.
They don't seem to show up on coinmarketcaps. (they do have rankings for exchanges)
And "easy to find" is another "good" thing about them.
Look at the exchange if they are requiring KYC. There are also exchange which do not forced their traders to have KYC procedure unless you will withdraw above 100 BTC. Cryptopia and Idex are best examples of this. I used these two exchanges already and I admit that they are quiet good and fast exchanges. Try also to look for bitforex. I found that they also not require KYC in small investors.