To hint to the girl that you like her, try to always be nearby. If you know that in the corporate dining room for dinner, she sits in the same place, try to come for lunch to her and sit at her Desk. Or get more in her favorite bar after work. In any case, make sure that she always saw you.
To hint a girl you like, you can use social media posts or emails. Just invite her out for coffee. It's quite simple.
Send her a little or non-binding gift showing what you care about it. For example, if you often notice that she's looking for writing accessories, put on her Desk a small box with a nice pen and a nice note stating that you noticed that she lost the handle and possibly would want to use this.
Try to look her in the eye and smile. This is the best way to hint to the girl that you like her, without words.
Use your manners to demonstrate feelings. If she enters the room - hold the door if she's going to get – push her chair for her. In any case, she will pay attention to your manners and appreciate what you are trying to make her life more comfortable. And this is a sure sign that you like her.