Actually is not easy at all!!!first of all you will need a translator,since nobody speaks even basic english in the foreign police office! Their website is also not so updated so you will have to make a question visit first to be 100%. Some basic documents you need to have is ID,Passport,Criminal record,Education Degree,if you are married or have kids you will need the certifications. Check out this websites
Articles to help you in your expat project in Slovakia