First, you mention the day or date of the birthday. Then you mention where you went to buy a gift or present for you friend. Later on, what did you wear to her party. When you are there, you explain how she dressed like and her feelings. The activities done at her party, how many people were there, and the food provided.
Then you explain, maybe how her house was decorated and her cake.You can mix all the points up if you want to. There are so many more that you can get. These are some I thought of. Hope they come in handy.