Name of friend
Address of friend
Dear (name of friend)
First paragraph: Introduction of the letter could be in the form of enquiring about his or her health or could be just stating that you are replying to the earlier letter. Include your feelings about receiving the letter.
Second paragraph: Exchange information. Tell the friend more about you and ask about your friend’s activities. You could also use this paragraph to motivate or seek support. Use casual language and keep it short. It should be like a conversation between two friends and the letter should flow very fluidly.
Third paragraph: End of the letter where you can seek a reply. State your feelings about being away from each other and encourage your friend to reply to your letter.
You can end the letter by casually signing as your friend or warm regards etc and add your name.