Countdown to your wedding day
10 to 12 months
If you haven't done it already, this is a good time to announce your engagement and introduce your respective families. Since most reception halls and churches have busy wedding schedules, it is important to book both as early as possible, preferably at least a year in advance of your wedding day. It's also a good idea to start putting together a guest list around this time and ask your parents whom they'd like to invite as well. Also, since your budget will determine almost every aspect of your wedding, sitting down and determining what you can spend - and developing a savings plan - should be first and foremost.
6 to 9 months
This is the time to start booking some services, such as a florist, caterer, a DJ or band, and a photographer. However, some of the more experienced DJs, bands and photographers might have their schedules booked a year in advance, so this is something you'll want to consider doing shortly after you choose a wedding date. Also, this is a good time to inform any guests who will be traveling significant distances of the date of your wedding. The earlier your guests can book a flight, the less expensive that flight will be. This is also a good time to order gowns for both the bride and bridesmaids, as some manufacturers require a few months to ship to bridal shops. You might want to ask someone such as your priest or rabbi to be the officiant of your wedding. And just as out-of-town guests will save travel dollars by booking flights early, you will likely save money, too, if you book your honeymoon early.
4 to 5 months
This is a good time to decide on a wedding invitation. Also, now is an ideal time to start hunting for a wedding cake by sampling a number of different bakeries and their cakes before ultimately making a decision. Just to be sure, confirm that all of the bridesmaids have ordered their gowns and start looking for a tuxedo for the groom and the groomsmen. If you haven't done so already, purchase your wedding rings and talk to the people that you would like to have participate in the wedding ceremony.
2 to 3 months
Finalize your guest list and mail out your invitations. If your guest list includes many people who are spread out geographically, mail the invitations as close to 12 weeks in advance as possible. This is also a good time to finalize your menu choices for your guests, and find all your wedding accessories such as the ring pillow, candles, etc. Also, since it is tradition to provide gifts for those in the wedding party as well as the parents of the bride and groom, this is a good time to decide on and purchase those gifts. Just to be safe, confirm that all groomsmen have ordered their tuxedos and finalize all transportation, both to and from the wedding and to the airport for your honeymoon.
1 to 2 months
Schedule the first bridalgown fitting. Also finalize the readings you'd prefer during the ceremony and mail them out to anyone who has agreed to do a reading. If your family prefers to host a small gathering for close family and friends after the wedding rehearsal, the night before the wedding, this is a good time to order any food or drinks you might want to serve that night, or make a restaurant reservation.
3 to 4 weeks
Confirm your honeymoon arrangements and see if your wedding rings are ready. This is also when you should get your marriage license and check the guest list to see who has and hasn't sent an RSVP. For those who have yet to RSVP, you might want to contact them so you can get a closer idea of what the head count will be. You should also prepare and order your wedding program around this time.
1 to 2 weeks
Get a final attendance count and submit it to the caterer as soon as you know it, while also providing a final seating chart. Pick up the wedding gown and tuxedo. Make sure the wedding party picks up their attire. Also, finalize your vows and confirm all wedding-day details such as transportation, photo schedules, and addresses. And don't forget to pack for your honeymoon.
The day before
This is mainly when you rehearse for the ceremony and make any final confirmations you might have to make. Also, make sure to get some sleep so you'll look good in all of your wedding-day photos. - (MS)