CloakCoin is traded on several digital currency exchanges.
Find an updated list in the Exchange section on this web site.
Some exchanges, i.e. Livecoin.net, provide the option to purchase CloakCoin directly with FIAT currencies like USD or EUR. Most exchanges offer Bitcoins/CloakCoin trade pairs. For these exchanges Bitcoins need to be acquired first which can be done on many exchanges, i.e. Kraken, Bitstamp, Bitfinex and others.
There is also the opportunity to get some CloakCoins for free at the Faucet!
When you own CLOAK you can earn interest with PoS staking (6% p.a.) and by supporting ENIGMA transactions.
For every ENIGMA transaction you help to process you earn a fee depending of the sent amount.
If you want to know how you can use CLOAK, read Use CLOAK.