Need help with kissing SOS

I'm getting to see my boyfriend tonight. We kissed once, well kissed three times for the first time, and he's more experienced than I am. My kisses sucked. I'm just new to all of it and how to pucker tbh. Surely it isn't that hard. I might just be physicing myself out. Can anyone try to explain to the best of their ability how I can somewhat make the best of it? Obviously practice makes perfect but I'm open to advice.