### Leap Year Checker

1. **Print a Welcome Message**
- Instruction: Print "Welcome to the Leap Year Checker!" to introduce the user to the program.

2. **Start an Infinite Loop**
- Instruction: Use `while True:` to start an infinite loop that will allow the user to check multiple years until they decide to stop.

3. **Prompt for Year Input**
- Instruction: Ask the user to enter a year with the prompt "Enter a year to check if it's a leap year: " and convert this input to an integer.

4. **Initialize Leap Year Check**
- Instruction: Check if the entered year is divisible by 400 to determine if it's a leap year.
- If the year is not divisible by 400, proceed to the next check.

5. **Check Divisibility by 100**
- Instruction: Use an `elif` statement to check if the year is divisible by 100. If true, the year is not a leap year.

6. **Check Divisibility by 4**
- Instruction: Use another `elif` statement to check if the year is divisible by 4. If true, it is a leap year.

7. **Final Check for Leap Year**
- Instruction: Use an `else` statement for cases where the year is not divisible by 400, 100, or 4, indicating it is not a leap year.

8. **Print Leap Year Result**
- Instruction: Print whether the year is a leap year. If conditions are True, print that it is a leap year; otherwise, print it is not.

9. **Ask if User Wants to Continue**
- Instruction: Prompt the user with "Do you want to check another year? (yes/no): " to decide if they want to continue checking another year.

10. **Check User's Decision to Continue**
- Instruction: Use an `if` statement to check if the user’s response to continuing is not 'yes'. If it isn’t, print "Goodbye!" and break out of the loop to end the program.