This depends on your schedules and availability, but seasonal changes make a major impact. If you want to take advantage of the local environment with outdoor festivities, check the average rainfall by month and ensure that you're not positioning your event right in the middle of hurricane or monsoon season. Be aware of fluctuations in tourism; high season translates to expensive booking rates and congested sights, but low season can mean getting the best rates and ammenities available.

Save-the-dates should be mailed 8 to 12 months before the wedding. "The official invites should go out no later than three to four months before. 

An extra-long lead time will allow guests more time to book their rooms and make travel arrangements.

Guests are traditionally expected to cover their own lodging and transportation expenses, but it's important that you make this as clear as possible. 

If you are working with a travel agent they will set up a website with all the details about available rooms, the number of nights available and the prices as well as a convenient way for your guests to make their reservations. If you've booked a hotel room block, emphasize that each guest needs to reserve their own room with your travel agent so that they are included in the block. 

You don't need to book anyone's travel, but it's a nice gesture to make the process easier by using a travel agent who will lighten the load by taking over handling all the reservations, inputting everyone's travel information and answering all your guests questions.

Making a marriage legal isn't quite as easy as hiring an officiant. Countries have different requirements necessitating a whole myriad of paperwork from birth and medical certificates, letters of intent, and even proof of residency etc. Speak to your travel agent about all the specifics at your choosen destination.In some cases, in most cases it is a lot easier to get a domestic marriage license and have a civil ceremony prior to your departure and then have a symbolic ceremony at the resort.