O-lifts done wrong are the fastest way to hurt yourself, or others around you. Start with the bar (bumper plates if you have them) and get your form down before attempting to add weight. When you do add weight, build up slowly.
Hell, you can practice form at home with a broom stick. That's how my coach started me on it - I just practiced the movement pattern for a few days without any weight. It's actually harder to have good form with a really light weight, so if you master the broom stick, you're good to go.
I would start by doing the two movements separately, so you can concentrate on form on each of them.