presenting to the king

Tomorrow I have a meeting for work. I will have to present one of my projects. Over the last few months I have been totally responsible for the project. I noticed that every time I have to do a presentation (for the municipality or the clients), a day in advance I get super stressed and scared that I will make a mistake. I might say the wrong thing or I will find out there are some mistakes somewhere. It feels as if I have to present to the king (or president ;)). That’s how nervous I am. Is there any way to make the stress smaller? I know having a bit of stress in this case is normal. But I guess this is a bit too much. Do you have any tips how I can reduce the stress? Change the thought?