Formats for informal letters:

1. Date
2. Greeting (Dear [Recipient's Name], Hey [Recipient's Name], Hi [Recipient's Name], etc.)
3. Introduction (How are you? I hope this letter finds you well.)
4. Body (Main content of the letter, sharing news, updates, thoughts, feelings, etc.)
5. Closing (Looking forward to hearing from you soon, Take care, Best wishes, etc.)
6. Signature (Your name)

General Format

- Salutation: Dear [Recipient's first name],
- Opening paragraph: Express affection, mention the reason for writing, or inquire about the recipient's well-being.
- Body paragraphs: Share personal experiences, updates, or ask questions. Use conversational language.
- Closing paragraph: Express your love, best wishes, or a reminder of your upcoming visit.
- Closing lines: With love, Warm regards, Your friend,
- Recipient's name: (Optional, if written on envelope)
- Sender's name: (Optional, if not written on envelope)

Example:

```
Dear Emily,

I couldn't resist writing to you after hearing about your exciting trip to Paris! It sounds like you had an amazing time. I'm especially curious to hear about the croissant you tried. I've always wanted to try an authentic French croissant.

Speaking of travel, I'm planning a road trip to the mountains next month. I can't wait to escape the city and spend some time in nature. Have you ever been on a road trip? If so, do you have any tips?

I miss you, and I hope we can catch up soon.

With love,
Katie
```

Additional Tips:

- Use informal language and contractions.
- Share personal anecdotes and show your emotions.
- Use emojis or emoticons sparingly.
- Proofread your letter before sending it.
- Consider the recipient's hobbies, interests, and current events when choosing your topic.
- Write in a regular pen or type the letter on a computer.