How am I going to leave her at daycare?!

Going back to work in a few weeks. My LO will be 4.5months old. I’m very happy with the daycare she’s going to and feel comfortable with the choice but, how on earth am I going to leave her? I cry just thinking about it! I want to go back to work, I love my job and am only going back part time...but I’m just dreading the day I drop her off. Any tips/advice/survival methods from you mamas who have started day care? Or just anyone going through the same thing? I’m having a hard time, I have no idea how I’m going to do this.