Check if you will need a passport or any visa to enter the country and that your passport is still valid. Most countries require your passport must be valid at least 6 months from the date of your return to your home.
Check to see what type of paperwork and documentation you will need to travel.
Check with your government concerning safety warnings for tourists at destination.
Do some research; learn as much as you can about your destination.
Check the weather of your destination for planning the trip accordingly.
Find out what type of diseases are common to the destination you will be visiting and take actions to prevent your exposure to those diseases.
Find out what types of vaccinations you will need to enter the country, there may also be medications you will need to take before, during and even after your trip.
Check the financial section of your newspaper, they usually post exchange rates and checking in advance can give you an idea of how much you will need to budget.
Check the dates of local major holidays or festivals, since services may be limited on those dates.
Do some research with your Customs to find out what you can take with you and what you may bring back.
Build some basic language skills in the local language.