The key to IVs is patience. Especially in the hospital setting where time is not always critical. I have been a medic for almost 10 years now working FD on the street, ERs, and now in the air. Working in the ER was the best way to dial in my IV skills since every Tom, dick, and Harry will get labs drawn. In this environment patience and confidence are key. Try to use 2 tourniquets if needed. Nice little trick. And when you get good at them by visualization, then work on them and get good at them by feel. That is one skill that I can say I have extreme confidence in. You will be fine. Good. Luck.