Once you have set up an IEP that is good for your child, make sure all services and accommodations listed in it are being done.
Remember that the school is legally required to follow the IEP!
Here's what you can do:
Talk to your child and their teachers about what's happening in the classroom. Make sure all services and accommodations are actually happening. This should be the case, but sometimes it's not. Remember that you have a right to get what the plan says!
Keep checking with your child that they are getting the help they need to do their best in school. Get in the habit of talking about this regularly. If there are any problems, it's much better to find out right away!
If you have any questions or concerns, talk to your child's IEP team.