A great review for some of us who forget...or for those who are anal in their writing.
Most of us need to review punctuation from time to time. Let's begin shall we?
If you want to write long sentences then use the period wisely. There is no magic to sentence length, but don't make too much work for the reader if you want your audience to read it.
If you are writing online, sentences should be short for those who scan.
The exclamation point
This one is used to show excitement, but don't over-use it or it will sound like you are shouting at the reader. William Zinsser says don't use it for humor, instead be more subtle. If you want to make a point it's better to restructure the wording.
Most of us used this to carefully balance sentences. It connects two sentences together. Many writers still use this, but it's "old school." A long dash is a more modern way to write two balancing ideas. Semicolons are still useful in very long sentences.
It's best used to list items. Again, it's kinda outdated like the semicolon. In it's use you can use the long dash, but be careful, the short dash is not the same thing. Use the colon for more formal documents and research papers.
The dash has replaced the colon and semi-colon in most writing today. Most of us didn't learn to write like this in school. The short dash pushes the sentence forward to amplify the second part of the sentence. The long dash is mainly used to add explanatory detail that would have required a new sentence. You can change the dash settings in what ever version of word you are using.
A good writer uses all of the above to add variety to written copy. If you aren't sure then check. I keep a copy of Strunk &White on my book shelf.