The exact first step depends upon the kind of documents you need authenticated. You have the visa straight away, the effort you put in is close to nothing, and it's not costly either, especially in case you use the Standard processing time. When the form is submitted, you can't make any changes.
Make certain you travel with all the suitable documentation, like your passport, GCC residency permit and Kuwait travel visa in any way times. Ultimately, the attestation is performed by the Embassy of Kuwait and then your document is about to be utilized in Kuwait. You may locate a certified translator by going to the American Translator's Association site.