You’re only as old as you feel
Age is just a number, and your actual age doesn’t necessarily reflect how young or old you feel inside.
Another year older, another year wiser
As you age, you gain more knowledge and experience. It's often said humorously on someone's birthday.
Age before beauty
A playful expression used when allowing an older person to go ahead of you, usually in a joking way.
A year older, a year bolder
With each passing year, a person grows in confidence and courage
Getting a year under your belt
Completing a full year of something, typically used to reflect on aging or experiences gained over the course of a year.
Don't count the candles, just enjoy the cake
Don’t focus on aging, just enjoy the moment and celebrations