Peace of cake,
Invitation letter ,
Passport size picture,
Insurance ,pay as you wish but not less than intended period of stay
Copy of ticket reservation,
Go to Holland embassy/Belgian as well,show them those documents and ask if they need more,but I think that it is.
And you must submit all documents 14 days before traveling day.
Do not expect too much in EC.
You just need to be best of the best to pass,especially having in mind your citizenship.
if you are only equal to others,others will pass.
So ,relax ,there is no special preparation for tests,except to work on english language. It might help,to listen bbc radio on the internet if you have good intenet connection. Just to "prepare" your ears.
If you pass it will be great job. you will never find anything simmilar in your "vilage" ,believe me.
and you always have PM function to ask me,
Best luck,
SINGA