You can create the equation using only four fours to equal 77 as follows:

$77 = 44 + 44 - 4/4$

This equation uses the number 4 exactly four times.

Would you like more details on this? Here are some related questions you might find interesting:

1. Can you write an equation using four threes to equal 27?
2. What is the largest number you can make using only four fours?
3. How can you express 100 using exactly four fours?
4. Can you form the number 7 using four fours?
5. How would you solve a similar problem using only four fives?

Tip: Using operations like addition, subtraction, multiplication, division, and concatenation can help form various numbers with a limited set of digits.