Make your final guest list on a spreadsheet. Leave spaces to indicate when you have addressed and set each piece of stationery you will be using. Also leave room to mention what gift was received from each guest to help you with your thank you notes.
Type your guest list. Handwritten lists leave too much room for error if you will be hiring a calligrapher or having anyone else help you address your wedding invitations and other wedding stationery.
Address each set of stationery all in one sitting. If you are addressing your invitations sit down and do them all at once to minimize errors. You will get into a groove and make fewer mistakes. Also you will be less likely to skip over someone or mark your guest list incorrectly. If you will be having a large number of guests get your intended spouse, mom, maid of honor or anyone with good handwriting to help.
If you would like specialty postage for your invites go online to the post office’s website and order it there after you have had your invitations weighed. This will save you from driving to multiple post offices to get the stamps you want in the quantities you need.
Only address your own stationery if you have good, legible handwriting. Take your time. If your cursive or printing is more like chicken scratch then anything legible, enlist a friend or two to help while you seal, stamp and assemble the invitations and other stationery.
Remember to use your new married name (if you are changing it) on your thank you cards, wedding announcements and anything sent after the wedding. It is not appropriate to use what will be your married name before the wedding.