Lots of Youtube videos out there. The way I started was with my dog heeling, then stop and put my hand vertically in front of her face palm toward her eyes, much like the stay signal a lot of people use. When she picked up the idea that when I stopped and did that signal she should stay standing and not sit, I added a name "stand". Whenever I worked with the stand I tried to keep with that command until I knew she understood by working a short course with only stand and circles (no sitting) before having her go to sit or down. I also use the stand command when grooming her so she will stand still for combing those long fluffy ear hairs. Clicker training is also very helpful but you have to learn to handle the clicker, treat, and leash all at the same time.
Have fun. Rally is a lot of good times. "Click your way to Rally Obedience" by Pamela S. Dennison is a great guide.