A checklist of other things to consider:
Before leaving, make sure not to leave any outstanding bills in your home country and make the necessary arrangements to pay any bills that may arrive after your departure. Take care of any rent/mortgage you may have and ensure that utilities are being paid while you are abroad. Notify important institutions like your bank of your change in address.
If you are retaining your bank account in your home country, enquire about fees for foreign transactions, additional credit card fees or any changes you need to make with your account. Inform banks that you will be using your credit cards while abroad, so as not to arouse any suspicions around the activity on your account, as anti-theft systems may consider transactions as unusual and block your account.
You should consider informing tax offices in your home country about your change in residency. Some countries may have reciprocal tax agreements that exempt you to pay taxes in your home country while you are away, while in some cases you may need to pay taxes both in your home country and abroad.
The National Tax Administrations will be able to advise you of what steps to take. American citizens should consult the IRS guide "U.S. Citizens and Resident Aliens Living Abroad" for information about filing tax returns while overseas.
Make sure you are up to date on routine vaccinations like measles-mumps-rubella (MMR), diphtheria-tetanus-pertussis, varicella (chickenpox), polio and a yearly flu shot. Some health authorities also recommend a hepatitis A vaccine to prevent disease from contaminated food or water.
For concerns about your health, the World Health Organization (WHO) publishes International Travel and Health which is available free online and is updated annually. MD Travel Health is another great resource which is updated daily and offers free, complete travel-health advice for every country.