What are the best practices for optimizing Solidity code for gas efficiency?

Optimizing the Solidity code for gas efficiency involves a number of best practices. Minimize storage use by preferring memory or call data since storage operations are expensive. Use smaller data types and pack variables tightly to fit them in storage slots. Precompute values wherever possible off-chain to avoid unnecessary computations. Loop iterations should be minimal, and complex logic should be simplified. Reuse instances of already deployed contracts to reduce the cost of deployment. Also, test and analyze smart contracts with Remix and Gas Reporter to look for code bottlenecks and improve gas efficiency.