It is very important for parents to pay close attention to their child's attempts to communicate, and to encourage these attempts. Here are some tips to use if you're having trouble understanding what your child is trying to say:
If you don't understand what your child is saying, encourage her to repeat it by saying things like "Tell me again" or "Tell me more."
If you got part of what your child said, repeat the part that you understood, and ask him to fill in the missing parts.
Watch your child closely. Watch for eye movements or gestures that might give you a hint about what she is trying to say.
You can also ask your child for help, and make it appear like you're having trouble hearing by saying things like "I didn't quite hear that" and ask him to say it again.
If after all of your attempts, you still can't understand what your child is trying to tell you, you may have to apologetically say that you do not understand.