It takes a little while to teach this-you've got the right idea, to give her treats each time. Start from just a short distance away, with a treat in your hand. Tell her, "COME", and when she does, give her the treat. If she gets easily distracted, or isn't enthused with her treats, up the anti-try cheese, baby carrots, the treats that smell like bacon, etc. And in the beginning, treat EVERY time. That way she'll associate "COME" with TREATS! Once she gets it, move farther away, or randomly call her from another room-carry around a pocket full of treats so you can do this. Sooner or later, she'll catch on. It's difficult to train them sometimes when they're really young-they get distracted easily
Best of luck!