I’m nervous

I’m a first year nursing student and for our health assessment we will have a 2 hours nursing duty today. I’m nervous because I’ll be handling an actual patient. If I mess up their bp and things something might go amiss. I want my first patient to be safe. I ain’t that good at taking vital signs yet. I know it might sound easy to some but I’m still confuse about things. I wanna be a good nurse… but I’m always nervous about everything.