It goes without saying.. Make sure the venue and reception date and times are secure before ordering invitations...

In a nutshell, here is a standard invitation layout etiquette:

or	The basic invitation may have just the invitation text, or text and a symbol or decoration on the cover. If there is a design, it should go on the front with the invitation text on the inside. If it's just the invitation text, the text goes on the front of the folded invitation.
	In general, the tissue paper goes next to the text, and enclosure cards and other inserts should be next to the tissue paper (so the tissue is in between the inserts and the text). This is a tradition from the days when ink would smudge and smear... the tissue served to protect the text.
	On an invitation where the text is on the front of the folded card, the tissue will go in front of it, rather than inside. The enclosures are then placed in front of that. Notice how the response card is placed inside the flap of the response-card envelope, but not inside the envelope.
	The entire collection of inserts is placed inside the inner envelope facing toward the back of the envelope. This inner envelope is addressed with just the recipients name(s) on the front.
	This inner envelope is then placed inside the outer (mailing) envelope, names facing the back of the envelope. Exclude first names on this inner envelope "Mr. and Mrs. Sam Shelby".
It's okay to omit any of the above except the invitation. You can do without the inner envelope even (although more informal). Tissue paper is nice and traditional, but can be omitted. Maps, schedules and rsvps are also nice, but optional. Most wedding invitations consist of a smaller, ungummed envelope inside the larger, mailing envelope The smaller envelope contains the invitation, tissue paper, list of events, and perhaps a map. The smaller envelope front faces the flap of the larger envelope. The rsvp card or envelope will go inside the larger mailing envelope, but outside the inner envelope usually.  Outer envelope should be hand addressed

Get a sample of the invitation, with all the fixin's. Check the postage on it. You can cut costs by coordinating the invitation so as not to go over one ounce.

Order extra envelopes in case of mistakes when addressing .

Usually the parent that raised the daughter is listed as the host .

Mail all invitations four to six weeks before the wedding date.

Important! It's worth it to include a postage paid rsvp letter or card (give them the stamp). Including just a card (rather than a complete envelope) is okay unless the wedding is very formal. You'll make up the extra postage cost in savings by not ordering additional $40 a plate catering than what you need.

For divorced parents, it's okay to list their first and last names, rather than Mr. And Mrs.

Spell out all numbers.

If including children in the invitation, write their individual names on the inner envelpe too... "Mr. and Mrs. Kevin Williams
Toby, Sharon and Jessica".

It's okay to add a special verse or song chorus that symbolized the theme for the wedding.

Don't write "and family" on the envelope or invitation if you want to exclude children from the ceremony.

Have a friend of someone who has time mail YOU an invitation, so your wedding day will be postmarked on the invitation you keep in your album .

Usually, about 7-10 percent of "yes" rsvp's don't make it to the wedding.

About 20-30% of guests will not make the reception .

Call any quests who you don't get a reply from. It's very important, economically, to know as soon as possible how many quests will be coming.

Should you put the grooms parents on the wedding invitation? You can if you want to… However, if the bride’s parents alone are paying for the wedding, generally only their names should be on the invitation.