Here are some tips from the University of California Berkeley Library on contacting and communicating with your elected official through letters or e-mail:

• Be Original: Consider writing your own original correspondence. While many organizations can provide you a pre-written letter or postcard that you simply sign, many legislators consider a thoughtful, original letter from a constituent worth 1000 of the pre-written letters. Feel free to use a pre-written letter as a base to rework with your own words.
   
• Stay Brief: Government officials are usually very busy. The maximum length of a letter/e-mail should be one page. Keep in mind that the letter will probably be read by a legislative aid, so a brief letter is best.
   
• State Who You Are and What You Are Writing About: Identify yourself as a constituent and why you are writing in the first place first paragraph. This will keep your letter brief. However, refrain from using lines such as "As a citizen and a taxpayer..." and never make a threat.  Also, if you know the bill name or number state it in the first paragraph.
   
• Personalize Your Letter/E-mail: If the legislation you are writing about will affect you personally, tell the legislator about it. Write a brief personal story about what the legislation will/will not do for you and/or your community.
   
• Personalize Your Relationship: The more you can personalize your relationship with the legislator, the stronger your letter/e-mail will be. If you worked on his/her campaign or donated money to the legislator or their party, say so. If you ever met the legislator, briefly mention this in your letter.
   
• Three Points: In keeping your correspondence short, consider making no more than three main points. Flush out your three strongest points and stick with them.
   
• Be Respectful: Taking a firm position on an issue is fine, but opening correspondence with "Dear Idiot" will probably get your letter sent straight to the garbage. Do not use profanity. Even if your legislator is not the person you voted for, remember to be respectful.
   
• Include Your Address in Your Signature, Even in E-mail: Legislators are busy people, and you should never demand a response. However, some legislators will take the time to write back, but they cannot if you do not include your address. Including your address also affirms the fact that you are a constituent.
   
• Proper Address: Below are the ways to address your letters:

Dear Mr. President:

Dear Mr. Vice President:

To The Honorable Senator [Name]:

To The Honorable Representative [Name]:

• Follow up: After you have contacted your elected official, follow up on what they did. If he/she voted the way you wanted, consider contacting them to thank him/her. If your legislator did not vote the way you wanted, consider contacting them and respectfully express your disappointment. In any follow-up letter/email, mention the fact that you wrote him/her before the vote was taken.