Rather random of you but I'll answer that to the best of MY knowledge. xD
Basically... Review what the other people have posted before you and see what emotions/actions they are doing. Take note of this as you write about how your character is seeing it as well as your interaction with the current event/situation. Do also take note that you cannot read people's minds so when noted by italics, which is more commonly used for when someone is talking to themselves in their heads, you probably won't know what they are thinking unless they actually say something except for the few silent moments on their part. So just try to flow with how everyone has written their posts (it tends to revolve around crap-loads of reading so be prepared xD). Adding some descriptive words about the environment at the time can also perk up your post as in a realistic sense, people tend to miss out on most details save for the more observant people. All in all... it's about flowing. Yeah, I ended up ranting... Shoot me. xD
Okay so.... we can take my sample I wrote up there as an example. So my character is staring out to the ocean where we 'supposedly' drop from. Your 'character' as finally emerged from the water and makes their way to the beach. You do whatever it is you do to get there, swimming fast or taking a slow pace, and when you get to the beach, you can rest or lay down on your back or pick your nose, it's all up to you as the writer. Then you see my character staring out over into the ocean and you decided you want to talk to them since they are the only other person, other than you, that is there. You walk over descriptively or as fast as you'd like and upon reaching their location. You initiate a chat log which would lead to the other person posting a reply to your chat. Something like that. Try to catch details as much as you can to give it a visual sense, since I, in my opinion, would rather see something colorful and/or descriptive (I think there IS a limit to being extremely descriptive but large amounts never hurt anyone 8D) then something bland and lacking in imagery. You want to catch people's interest in your writing and if you dazzle them, hell that's a bonus. It all comes with practice and reading other people's posts. They can really give you a good idea how to write a storm occasionally as well as sentence structuring or even descriptive words you've never used before.
Oh hell... I ranted EVEN MORE. *O*
