Open file explorer and in the address bar type %appdata%
Find the .minecraft folder and click on it
These images are huge aren't they. I can't seem to work out how to resize them. Anyway, continuing along.
Click on the saves folder which will open all the folders for each of your world maps.
Copy the one you want to share, and save to a more accessible place such as your desktop.
Right click on the file, and select SEND TO >> COMPRESSED (Zipped) FOLDER
This will create a zipped file which you can upload to any file sharing website.
The main site used is mediafire.
Once you have the link for your file, you can share this online in our forums. Just select which forum best suits your map.
We may then upload your map to our server and livestream from there. You could even join us live on our stream. We livestream from worlds that have been uploaded to our site weekly, so stay tuned, yours could be next.