Make A List

• Create a list of everyone who hasn't responded to your invitation. Include their contact information so you can easily access it when needed. It's easiest to do this on the computer. Print your list out.
  
  

Delegate the List

• If some of the people are from the groom's side and some from the bride's side, separate the guests. Then go through and specifically analyze who the people are. One might be your mother's best friend, who she can easily call. Another might be a co-worker you'll see, and so on. Breakdown the best method of contacting each person so it doesn't seem like you're being rude (some people might take a phone call as being too much).
  
  

Post or Email

• If you have a wedding website, post a message asking people to RSVP. Send anyone who hasn't yet responded an email, if possible.
  
  

Make Phone Calls

• When all else fails, or you have no other means of getting ahold of people, pick up the phone and make some calls. Explain that you don't mean to be pushy or rude, but you simply need to give the caterer or venue a number. If someone is offended, try not to worry about it. It's your day and you have lots of other things to think about. Get your list squared away as soon as possible and move on with your plans.