In Role Play we sometimes have to sit and ponder a thought... what will I or how will I post my entrance?
First thing is make a profile... I posted simple directions on the Character Profile.  After, once the profile is up... go to the Realm Story Lines and get to business.. take your time thinking of a story.  Name it and go.  It should consist of detail on the character, environment, and a bit of history.  Followed by what he is doing, why, when, and where.  Even how.
Yes.. it seems confusing at first.. but it helps to better get into a story if it has the right amount of detail.  Please don't make it so short someone has to ask what is going on or how to jump in or what happened before or during.  Keep it simple if you like, but add spice to your entrance as well when adding to anothers storyline.  Don't assume leadership in someone else's storyline.  Leadership in a storyline is when you make your own for others to join.  You are then the moderator.  The one who created the story for others to follow.  So follow the simple laid out rules.. and there you go.. you have your first main story as well joining others.