As I'm writing this, I'm thinking of my birthday coming up on the 17th. No, I'm not trolling for birthday wishes but instead thinking of celebrations that go along with anyone's birthday. While some people like to make a spectacle of their birthday (my wife celebrates all month as if it's her birthday) others may not celebrate at all.
Often, we feel obligated at work to do some sort of recognition of this day. If you've ever tried to set something up with office politics and trying to celebrate each person individually...I feel for you. It's basically a wash most times as people either feel like "someone else got more" or "they forgot" or even sometimes "that was cheesy" type of feel.
So, what should you do for people?
First, don't put this on entire teams or team leads to figure out what to do. They have enough going on with supporting others and this should be coordinated by someone specific. Either HR, potentially leadership given the size of the company, or even a wellbeing/culture coordinator. These people will come up with the idea, logistics, and coordination to ensure things continually go smoothly.
Next, make it standard across the board. Manager? First week employee? Owner of the company? They should all be celebrated the same. Birthdays have no titles, so keeping it standard may feel like you're not doing something special, but the gift portion of it isn't the key...
What we normally recommend is to start off at a $10 gift card along with a standard card to be given to the employee. In that, take the time to write a heart-felt note. Don't do this the same day - take time to sit down, think about the employee, include details about their life and tell them how special they are. This is critical: Do NOT talk about their work performance regardless of how great or bad they are. Focus on them as a person, not an employee. Birthdays are here regardless of work, and turns out treating people like...people...is something important. It's best if the card and gift card is provided to the supervisor and the supervisor puts the words to the card but if that isn't available getting someone from leadership is the next best thing.
Recognition is important, even if it is a coworker or manager. Take some time this year to get to know your employees so these cards (and your relationship) is more meaningful. Maybe even get creative with the outside of the card with decorations, drawings, etc. It's a fun way to come closer with your employee.