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1. Install Joi: npm install joi

2. Import Joi: const Joi = require('joi');

3. Create a Joi schema for password validation:

   const passwordSchema = Joi.string().min(8).pattern(new RegExp('^[a-zA-Z0-9]{3,30}$'));
   

   The above schema specifies that the password must be at least 8 characters long, and can only contain letters and digits.

4. Use the validation schema in your React component:

   const [password, setPassword] = useState('');
   const [passwordError, setPasswordError] = useState('');
   
   const handlePasswordChange = (event) => {
    setPassword(event.target.value);
    const { error } = passwordSchema.validate(event.target.value);
    setPasswordError(error ? error.details[0].message : '');
   }
   
   return (
    <div>
      <input type="password" value={password} onChange={handlePasswordChange} />
      {passwordError && <div className="error">{passwordError}</div>}
    </div>
   );
   

   The above code sets up a state variable for the password, and a separate state variable for the password validation error. The handlePasswordChange function is called whenever the password input is changed. It uses the Joi validation schema to validate the password, and sets the error message accordingly.

   The error message is displayed below the password input whenever there is an error.

Overall, implementing password validation using the Joi schema in React JS involves installing Joi, creating and using a Joi schema to validate the password input, and displaying the error message when there is an error.