Tips

Here are some of the things that I personally recommend!

#1

-Always be subtle with your changes, you don't want to do anything super drastic, because you may not be able to make it look like the original again, and take my word for it, its annoying to have to press Ctrl+z to erase everything you have done.

#2

-Never use a tool that you don't know how it works, because it may end up putting a hole right through the map! You don't want to waste your hard work. But if that does happen, just press Ctrl+z and that will erase whatever you had done within one click.