I went to Big Bear in northern California once to go skiing with my cousin. I came back so sore from that xD.
Getting off the ski-left was tough for me too when I was there. Mostly because that was my first time skiing. The lift goes by quick, so be prepared xD. Like what Lineesa said, just gently push yourself off and try to balance. You will fall or tumble a couple of times, but don't worry, you'll get the hang of it. My cousin said it helps to lean your body a little bit forward when you're almost at the top.
Hope you have fun skiing!