Make a character, toodle around town for a while, get to understand basic commands, maybe even get into combat. Once you feel more prepared, really start getting into it. It'll come natural.
Use the help systems. Read "@newbie" and "@rules". Examine people, places and things wit the "examine" command. Search in the Sindome website search field above for "how do you progress in the game". Welcome and have fun!
You are here to have fun, but fun in a roleplay intensive multiplayer game is a much broader goal than it is in an fps or even an MMO. You must consider not only yourself, but others as well; likewise, they should do the same to you. Characters may be selfish, greedy, cruel, harsh, brusque and want to win at all costs. As a player, we should be the exact opposite. We're all here to participate in a live, interactive story which has no end and provides countless opportunities for us to experience and explore mindsets and characters to our heart's content. Thus, I think the most important and basic thing I could offer to you is to remember to be kind and patient with your fellow players; make sure they're able to trust you and feel comfortable in all scenes (well, at least from a perspective of playing; certainly, uncomfortable but not abusive/out-of-line IC actions may make a player feel unnerved - but that is a good thing), and know you're here to be inclusive in your character's story.
I hope, in turn, you will find yourself greeted with the same in most of your encounters. If you do, I think you'll see even the steepest of learning curves become easier to navigate, and you'll get the hang of it in no time. Shyness, embarrassment and time are your only obstacles and two of them are able to be conquered.
Unless you've found a time machine, then, well. I'm jealous.