Staking cryptocurrencies is a process that involves committing your crypto assets to support a blockchain network and confirm transactions. In return, you are rewarded with more cryptocurrency.
All delegators to all validators run the risk of slashing. This can happen when a validator breaches the protocol or becomes unelected due to low stake.
On paper, this could happen when a validator is Double Signing. When doing so, the validator loses at least 2% of the stake depending on the number of corrupted slots.
In practice, this has never happened before on the entire Harmony blockchain, but the risk is still present.
You can delegate ONE to BoxedCloud.net with one of the supported wallets listed here.
Here is an article that guides you step-by-step: Link.
It takes about an epoch or two (~48 hours) for the first rewards. Note that the validator has to be Elected to make rewards.
Rewards are based on the amount of slots a validator has. In addition, factors such as the validator's stake, the total amount of ONE staked on the chain, and shards' performance influence rewards. These factors change with each epoch.