Solo staking means running your own validator with the full 32 ETH required, plus dedicated hardware and reliable uptime. It offers the highest degree of control, no third-party fee, and directly strengthens Ethereum's validator decentralization, but it demands technical competence and carries direct slashing exposure if you misconfigure your setup.
Pooled staking — through an exchange or a staking-as-a-service provider — removes the technical burden and the 32 ETH minimum, letting you stake any amount. In exchange, you pay a fee or commission and, for custodial options, trust the platform with your funds instead of holding keys yourself.
Liquid staking sits between the two: your ETH is pooled with others and staked non-custodially through smart contracts, and you receive a liquid token (like stETH or rETH) in return. You keep more composability than exchange staking (the token is usable across DeFi) while avoiding the technical overhead of solo staking, at the cost of protocol and smart-contract risk.
There is no universally 'best' option — the right choice depends on how much ETH you hold, your technical comfort level, whether you want liquidity during the staking period, and how much counterparty or smart-contract risk you're willing to accept.