Install @reduxjs/toolkit and react-redux, create a slice with createSlice, configure the store with configureStore, wrap your app in a Provider, read state with useSelector, dispatch actions with useDispatch, and handle async with createAsyncThunk.

Use createSlice, defining the initial state and reducers in one place. It auto-generates action creators for you. A cart slice might have an items array and add and remove reducers.

Use the useSelector hook from react-redux, selecting only the part of state you need. Selecting only the slice you need avoids unnecessary re-renders when other parts of state change.