You basics? You got em. c:
FIRST THING.
Do you have any custom items? Things you downloaded? If you do, you must place them in their own custom object file. You can do this by saving each item to the new object file in object maker, then editing your .object file in the map's terrain folder.
NEXT THING.
Export. Take all the stuff that the export made, copy it and put it into a brand new folder on your desktop. Place any other things not included in the export in as well, such as custom sounds, music, water textures and such. Place a "Readme" file (text document) in there for good measure telling downloaders where to put what.
DISTRIBUTE.
Upload to mediafire.com
Give the link to friends. No, people don't just materialize in your map. It is not a public map, so the only way they can get in is by downloading it. You need to invite them and share the file.