[quote=@Rhymer]Don't wait for inspiration. Writing is damn hard work and it requires paramount focus. Go for it.
[/quote]

This. 

What works for me right now is to read through my partner's post, imagine it, feel it, and see what strikes my fancy - see what inspiration gives me, so to speak. I would have specific points I want to include in my reply, I note them down, and then - this is where hard work begins - I sit myself down and churn out a first draft of my post. Ugly and crude like a troll baby it usually is; I write whatever my mind comes up with to get it out of the way. What I find difficult is not judging myself and to let it go, to free flow my writing, so that I will have [i]something[/i] to work with later on. Then the day after, I will smooth out the scene I have in a second draft, and I will polish it up again another time. 

If, for some reason I cannot write out a scene, it feels boring and sluggish, then I concede that maybe it isn't what I want to have - subconsciously I want to go in another direction. There's nothing wrong with chucking out the first idea in favour of a more exciting prospect. 

It is hard work. It needs practice. And like every hobby and skill you want to learn, it gets easier and better with every session, however short it may be. 

That said, I can't play in a group RP. It's too fast paced and/or too much filler goes on in them, so my preferred medium is 1x1. You may need to find out if it's the rate that gets you or a personal laziness you want to whip into shape.

[img]http://37.media.tumblr.com/7e3025dd4790a0a162b2d098609c4cb0/tumblr_n6m3b4kDzX1qgwefso2_500.gif[/img]