Begin work on your dossier, or set of legal documents. Ask the agency you've chosen for a list of needed paperwork for Guatemala. Be sure to ask for two or three copies of your marriage license, birth certificates, and other legal documents. You will also need them for your home study.
Don't count on being able to use the same marriage license for your dossier that you use for your home study. Some countries will want original documents only. If you plan on adopting more than one child, some countries require a dossier for each child. So plan on erring on the side of caution and get more than one copy. You never know when you might need them.