Create a pile/stack of all of your invitation components.  The invitation should always be on the bottom of this stack because it is typically the largest item in your envelope and because it is the most important.  If your invitation is a flat card or a folded card with text printed only on the outside, then all remaining invitation components should be placed on top of the invitation.  If, however, your invitation is folded with text on the inside of the invitation, then all remaining invitation components should be placed inside the folded card. 

The first item that should be placed either directly on top of or inside the invitation is the piece of tissue paper (if applicable).  This is followed by your invitation inserts in order of importance and/or size.  The most important insert should be placed directly on top of the invitation (typically the reception card).  This, of course, means that the least important insert will end up being at the top of the pile.  I like to think of this as building suspense for your guests.  They have to look through all of the less important things before they get to see the most important thing - the invitation.

The typical order of items would be as follows:

(bottom)
Invitation
Tissue (if applicable)
Reception Card
RSVP Envelope (with back flap facing up - tucked around the RSVP Card)
RSVP Card
All other inserts in order of size with the smallest on top
(top)

All of these items should be oriented so that their printed sides face toward the back flap of the envelope that they are in.  If you are using an inner and outer envelope, then the inner envelope should be placed inside the outer envelope with the front/printed side of the inner envelope facing toward the back flap of the outer envelope.

While the above is the correct way to assemble invitations based on traditional etiquette, most modern brides do not follow these instructions.  The more modern method of assembly uses the invitation on the top of the pile and all of the other inserts (in no particular order) underneath the invitation.  Use whichever of these methods works best for you and fits the most with the type of wedding you are planning.  There is no right or wrong way.  Here are some other important general tips to keep in mind while assembling your invitations:

• Count each item before beginning assembly.  This way you know exactly how much of each item should be left over (if any) at the end of the assembly process.
• Place stamps on your RSVP envelopes before beginning assembly.
• Create an assembly line by making individual stacks of each invitation component in the order that they will be inserted into the (inner) envelope.
• For folded invitations, the fold should be placed inside the envelope first (this allows the card to actually hold all of the invitation inserts together).
  
• Inner envelopes should never be sealed.
• Outer envelopes should not be sealed until all invitations have been assembled and all inserts have been accounted for.
  

Ask your parents, your fiance's parents, and/or your bridal party to distribute the information verbally to anyone who asks. The main problem with this method is that some people will simply not ask for your gift registry information and then they will give you either monetary gifts (okay) or ugly crap from a store you would never shop at without a gift receipt (clearly not okay).

Add your gift registry information to your wedding website and then provide the URL of the website on your save the date or on an insert that you include with your invitation.  The wording for the insert could be something like the following:  "For additional information on our wedding including accommodations information and gift registry information, please visit our wedding website at: http://www.mywedding.com/SallyandJoe/index.htm".  You don't even need to mention that gift information will be available on your website if you are worried about offending some of your guests.

Include a nicely worded gift registry card with the invitation.  This card could say something like the following:  "The best gift of all will be your presence at our wedding, but if you would like to get us a gift, we are registered at: Macy's and Williams and Sonoma".  This obviously goes against all etiquette guidelines, but if you are sure that your guests will not be offended by such a card then there is no harm in including one.  If you are concerned about offending certain guests, you can always leave the card out of their invitations.

Outer: Mr. and Mrs. Robert Smith
Inner: Mr. and Mrs. Smith

or

Outer: Ms. Sarah Smith
Inner: Ms. Smith and Guest

or

Outer: Mr. and Mrs. Robert Smith
Inner: Mr. and Mrs. Smith
          John, Mary, and Michael (these are the children)

Now for the more fun, non-"etiquettely" correct ways of limiting the number of guests invited to your wedding.  There are a few different ways you can use your RSVP card to accomplish this goal.  The first idea would be to include a sentence at the bottom of your RSVP card like the following:

"We hope that the two of you will be able to join us." 

The second idea would be to include a line on your RSVP card like the following:

"_____ of 2 will attend"

If you are specifically choosing to limit your wedding to only adults, you could discreetly include one of the following phrases at either the bottom of your invitation or at the bottom of your reception card:

"Adults only" or "Adult reception" 

Finally, you could simply ask your parents and/or your bridal party to mention to your guests that children are not invited or that the number of people you can invite is limited by your reception location (may be a lie, but at least it will prevent people from being angry at you).

• The due date of your final head count to your caterer or reception site

• The number of invited guests

• Your family and your fiance's family

• The RSVP method (i.e. phone, email, webpage, or snail mail)

Let's go through each of these bullet points separately...

The due date of your final head count.  If your caterer/reception site has requested that they receive your final head count (i.e. number of wedding guests) two weeks before your wedding date, then you must actually know that number two weeks before your wedding date.  Therefore, your RSVP date must be, at a very minimum, 2 weeks and a day before your wedding date.  You get the idea...

The number of invited guests. If you are only inviting 20 people to your wedding, it won't take you very long to receive and count your RSVPs.  When there are only 20 invited guests and we make the assumption that 10% of all invited wedding guests neglect to RSVP or do not RSVP on time, that means there are only 2 people that you will need to phone or email to determine if they will be attending the wedding.  This amount of personal follow-up will probably only take you a few days.  If, however, you are inviting 250 people to your wedding and we assume the same 10% failure rate, that means you will have to follow up with 25 guests which will take considerably more time.

Your family and your fiance's family.  This seems like a strange thing to consider when determining your RSVP date, but it is, nevertheless, extremely important.  You know your family and, hopefully, your fiance knows his/her family as well.  Ask yourself these questions: How responsive are your families?  Will they respond in a timely manner?  Or will you have to personally follow up with most of them?  Will they invite extra people to the wedding (i.e. people who were not specifically mentioned on the invitation envelope)?  Will you then have to call them and explain that it costs you $200 to feed each guest and you really can't afford those extra people that they have invited?  If your family or your fiance's family is, shall we say, a more difficult family, then you may want your RSVP date to be a few weeks before your head count is due to the caterer.

The RSVP method.  The most traditional and the most widely used RSVP method is the snail mail method.  These days, however, many couples are choosing to receive RSVPs by email or website submission (see www.favorofareply.com as an example) as the cost of stamps increases (42 cents!) and the percentage of internet-savvy wedding guests increases.  If you choose the RSVP snail mail method, you should give yourself more time to receive your RSVPS, than if you choose the website or email RSVP method.  This is just common sense.  If you are receiving RSVPs via snail mail, then there is always a chance that something will get lost in the mail or that your guests will actually mail their RSVPs out on the RSVP date instead of before.  If you have a lot of out-of-town guests, this could mean that you may not receive many of your RSVPs until a week after your RSVP date.  If, however, you choose to receive RSVPs by email or website submission, then even if your guests wait until the RSVP date to respond, you will still receive their RSVP on time.

Let's review with an example:

John Smith and Betty Johnson are to be wed on August 15th, 2008.  Their final head count is due to their caterer two weeks before their wedding (August 1st).  They are inviting 250 very unresponsive guests to their wedding.  Because of the large number of guests they are inviting and the nature of those guests (procrastinators), they are allowing three extra weeks to receive their RSVPs, count their RSVPs and follow up with their guests.  This puts their RSVP date on about July 11th (or 3 weeks before August 1st).  Since John and Betty are using snail mail RSVPs and they have a few out-of-town guests, they have decided to allow an additional week for postage delays.  This means that John and Betty's wedding RSVP date will be on about July 4th or 6 weeks before their wedding date.