To create an inset block, indent all items to be inset by 2 tabs (8 spaces)
To manually insert line breaks, add 2 spaces to the end of a line
To escape a character (let's say you want a # to appear, but it indicates a header in markdown) use the \
To create a numbered list just add 1. before each item in the list, markdown will automatically convert the ones into the correct number. This is nice when your list keeps changing as you are editing so that you don't have to re-number everything.
Here's a good reference: