Make sure to have eye-contact with the child when giving an instruction. Keep instructions as simple as possible, using as few words as necessary. Always give instructions in a clear, strong voice.
Positive statements are generally easier to understand.
Establish a few firm rules that your child can understand . Decide which rules are most important to you, and make sure that your child understands them. Repeat the rules often, and praise the child for obeying them. Let the child know immediately when one of these rules has been broken. Do not change the rules from day to day, but add rules gradually as the child seems to be able to keep them well.