Asterisks, hyphens or underscores can be used to emphasize text. Use this correctly, according to standard style, but use three dots, or periods. This is like underlining in manuscript writing style. As I mentioned before, add blank lines between paragraphs. The added white space makes it so much easier to distinguish one paragraph from the next.
Many people advocate indents.
I don't do it except in special cases. Generally the blank line is enough separation. . . . Two or three spaces are sufficient. Experiment and see which is more attractive to you. If you want to force an indent use two underscores and a space, or three to four dots.