You can stake CELO using whatever crypto wallet you keep your CELO in, including Celo’s own wallet. Often, there will be an option to lock a certain amount (meaning that you can’t sell it until it’s unlocked), and then you will choose — or “vote” for — a validator group that you want to stake. Validators are computer hubs that secure the blockchain. You’ll then need to activate and confirm your votes in the wallet. Once that’s done, your staking has begun. To stop staking, you’ll need to revoke your vote in the wallet, at which point it will be unlocked, you’ll be able to collect your reward for supporting the system, and — maybe most important — ou’ll be able to sell your holdings.