You will need a BitShares account to receive, hold, and use WhaleTokens. Although you can create a BitShares account at any of the exchanges. I recommend to use the RuDEX Exchange to create an account. Once you create an account, you can use any of the exchanges.
You can earn Whaletokens by attending community events and entering sponsored contests.
You can buy and sell WhaleTokens on the bitshares exchange, but please note that most WhaleTokens traded on the exchange are being sold by those who have won or earned them. Most WhaleToken owners don't sell their tokens directly but give them out as rewards for participation in community events and functions.
Find out more by joining the Official Whaleshares Discord channel.