Thank you all for all the questions you had that let me understand better how to do the test. Also to Kathy Sierra and Bert Bathes for their excellent book Head First Servlets and JSP which from my point of view is the ultimate book to get certified.
Sure, well first of all I have a little experience developing web applications, but the ultimate advice I can give is to grab a copy of Head First Servlets & JSP and read many tips located here in the forum about how the test is and you'll get it.