This is a training post I have used on many forums.

The story telling style is what you will see most on Role Playing forums due to the nature of forums and people replying. It gives RPers more to work with, and is easier for more people to join at will than a tag-based RP or to catch up if they have been offline for some time.
 
The basic use of the Story telling style is just that, to tell the story, unlike tag based story telling tend to be A LOT of heavy reading, and a lot of description, however this allows for A LOT more story to be read at once, and allows for quicker plot progression all at once.

Pretty much everything comes under the one element of story writing. Everything can be done in one flowing movement, so to speak. For example when your character speaks, he speaks with quotation marks on either side to show they are speaking. Generally with speech, there will be an "introduction" to them speaking. For example:

Sirus turned to his friend, muttering a few words, "You know, I really dislike this guy."

Just by that one sentence, you have been able to say who it is, who he's talking to, how he's saying his words, and what he's said. That's the flowing movement.

Actions in story telling style will always be descriptive. Unlike tag based where using emotes is quick and generalized, with story telling you need to be a little more precise.

Because this will be written like a book, you get a little more freedom to type then you do with tag-based. But however, compared to the easier to follow tag based, you need to remember that people will need to be able to read what you have written and understand what you mean, and that it is relevant to the plot.

If you're doing a scene with someone else and your character is interacting with them, then you need to leave "open ends". Open ends basically give the person you're wanting to respond a place to retort with their own character. See the following example.

As they waited, Sirus walked over to Aira with his arms open, ready to hug her.

Now, Sirus isn't hugging her yet, which gives me the option to either let Sirus hug Aira, or perhaps have Aira knock him away and not want the hug. Most of the time, you want to keep things open for other RPers, as RPers generally do not like having their characters forced into actions.

You can have "closed ends" as long as it's something that can be left open later. Again, using the hug example:

Sirus walks over, putting his arms around Aira and hugging her

Sirus is now hugging Aira. I can do something with this, but I'm restricted to the action being revolved around the hug. Examples of actions would be Aira squirming uncomfortably as shes hugged, or Aira quickly shoving Sirus off and stepping back from the hug. This means you have retorted but now you have to wait for the other to respond to the reaction of the hug, so use closed ends only if you know that the person you are doing it to has space to work.

I wont put an example RP as this site is littered with them, so happy hunting.

Any questions or additions feel free.