One of the basic "ingredients" for broadcasting a virtual event is a good internet connection. It is important to understand that even if you have a "high speed" internet, it does not automatically mean that you have an optimal connection to film your performance and broadcast it on the web.
Simply put, your internet plan is separated into two parts: the download speed from the web to your computer and the speed of sending data from your computer to the web. It’s this second that’s important when making live videos.
Aim for a minimum sending speed of 10mbits/s, so the visual and audio quality of your streaming will be good. However, 15Mbits/s is far better to ensure your event goes well.
Several options are available to test your connection, including this one. You have to look under Upload to verify the sending speed.
** PRO TIP **
Get out your ethernet cable! To have a performing live video, nothing beats the direct connection between your router and your computer. The advantage of wired connection versus Wi-Fi is its stability. Therefore, your video will keep the same quality throughout your performance.
MOST IMPORTANT if you're using a Wi-Fi connection, make sure the connection is only used for streaming your video. This means that no one else on your network should be streaming (Netflix, Amazon Prime, Youtube, etc.) and no one should be playing online video games during your broadcast!
Here's a video to explain some internet related streaming concepts.